diff --git a/timber-sample/src/main/java/com/example/timber/ExampleApp.java b/timber-sample/src/main/java/com/example/timber/ExampleApp.java
index 15e2c8ec3..e7d8cb48e 100644
--- a/timber-sample/src/main/java/com/example/timber/ExampleApp.java
+++ b/timber-sample/src/main/java/com/example/timber/ExampleApp.java
@@ -3,6 +3,9 @@
 import android.app.Application;
 import android.support.annotation.NonNull;
 import android.util.Log;
+
+import java.util.Map;
+
 import timber.log.Timber;
 
 import static timber.log.Timber.DebugTree;
@@ -15,6 +18,7 @@ public class ExampleApp extends Application {
       Timber.plant(new DebugTree());
     } else {
       Timber.plant(new CrashReportingTree());
+      Timber.plant(new StructuredLoggingTree());
     }
   }
 
@@ -36,4 +40,20 @@ private static class CrashReportingTree extends Timber.Tree {
       }
     }
   }
+
+  /** A tree which logs important events in a structured format. */
+  private static class StructuredLoggingTree extends Timber.Tree {
+    @Override protected void log(int priority, String tag, @NonNull String message, Throwable t) {
+      log(priority, tag, message, t, null);
+    }
+
+    @Override protected void log(int priority, String tag, @NonNull String message, Throwable t,
+                                 Map<String, Object> metadata) {
+      if (priority == Log.VERBOSE || priority == Log.DEBUG) {
+        return;
+      }
+
+      FakeCrashLibrary.log(priority, message, metadata);
+    }
+  }
 }
diff --git a/timber-sample/src/main/java/com/example/timber/FakeCrashLibrary.java b/timber-sample/src/main/java/com/example/timber/FakeCrashLibrary.java
index b77c77d4f..d47f693b6 100644
--- a/timber-sample/src/main/java/com/example/timber/FakeCrashLibrary.java
+++ b/timber-sample/src/main/java/com/example/timber/FakeCrashLibrary.java
@@ -1,11 +1,17 @@
 package com.example.timber;
 
+import java.util.Map;
+
 /** Not a real crash reporting library! */
 public final class FakeCrashLibrary {
   public static void log(int priority, String tag, String message) {
     // TODO add log entry to circular buffer.
   }
 
+  public static void log(int priority, String message, Map<String, Object> metadata) {
+    // TODO add log entry with metadata
+  }
+
   public static void logWarning(Throwable t) {
     // TODO report non-fatal warning.
   }
diff --git a/timber-sample/src/main/java/com/example/timber/ui/DemoActivity.java b/timber-sample/src/main/java/com/example/timber/ui/DemoActivity.java
index 34df2aeec..9aae5a811 100644
--- a/timber-sample/src/main/java/com/example/timber/ui/DemoActivity.java
+++ b/timber-sample/src/main/java/com/example/timber/ui/DemoActivity.java
@@ -5,6 +5,9 @@
 import android.widget.Button;
 import android.widget.Toast;
 
+import java.util.HashMap;
+import java.util.Map;
+
 import butterknife.ButterKnife;
 import butterknife.OnClick;
 import com.example.timber.R;
@@ -24,6 +27,10 @@ public class DemoActivity extends Activity {
   @OnClick({ R.id.hello, R.id.hey, R.id.hi })
   public void greetingClicked(Button button) {
     Timber.i("A button with ID %s was clicked to say '%s'.", button.getId(), button.getText());
+    Map<String, Object> eventMetadata = new HashMap<>();
+    eventMetadata.put("event-type", "button-pressed");
+    eventMetadata.put("button-id", String.valueOf(button.getId()));
+    Timber.v(eventMetadata, "This is an example of a structured log");
     Toast.makeText(this, "Check logcat for a greeting!", LENGTH_SHORT).show();
   }
 }
diff --git a/timber/src/main/java/timber/log/Timber.java b/timber/src/main/java/timber/log/Timber.java
index a927276b5..78445d849 100644
--- a/timber/src/main/java/timber/log/Timber.java
+++ b/timber/src/main/java/timber/log/Timber.java
@@ -7,6 +7,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import org.jetbrains.annotations.NonNls;
@@ -23,91 +24,186 @@ public static void v(@NonNls String message, Object... args) {
     TREE_OF_SOULS.v(message, args);
   }
 
+  /** Log a verbose message with metadata and optional format args. */
+  public static void v(Map<String, Object> metadata, @NonNls String message, Object... args) {
+    TREE_OF_SOULS.v(metadata, message, args);
+  }
+
   /** Log a verbose exception and a message with optional format args. */
   public static void v(Throwable t, @NonNls String message, Object... args) {
     TREE_OF_SOULS.v(t, message, args);
   }
 
+  /** Log a verbose exception and a message with optional format args. */
+  public static void v(Throwable t, Map<String, Object> metadata,
+                       @NonNls String message, Object... args) {
+    TREE_OF_SOULS.v(t, metadata, message, args);
+  }
+
   /** Log a verbose exception. */
   public static void v(Throwable t) {
     TREE_OF_SOULS.v(t);
   }
 
+  /** Log a verbose exception with metadata. */
+  public static void v(Map<String, Object> metadata, Throwable t) {
+    TREE_OF_SOULS.v(metadata, t);
+  }
+
   /** Log a debug message with optional format args. */
   public static void d(@NonNls String message, Object... args) {
     TREE_OF_SOULS.d(message, args);
   }
 
+  /** Log a debug message with metadata and optional format args. */
+  public static void d(Map<String, Object> metadata, @NonNls String message, Object... args) {
+    TREE_OF_SOULS.d(metadata, message, args);
+  }
   /** Log a debug exception and a message with optional format args. */
   public static void d(Throwable t, @NonNls String message, Object... args) {
     TREE_OF_SOULS.d(t, message, args);
   }
 
+  /** Log a debug exception and a message with optional format args. */
+  public static void d(Throwable t, Map<String, Object> metadata,
+                       @NonNls String message, Object... args) {
+    TREE_OF_SOULS.d(t, metadata, message, args);
+  }
+
   /** Log a debug exception. */
   public static void d(Throwable t) {
     TREE_OF_SOULS.d(t);
   }
 
+  /** Log a debug exception with metadata. */
+  public static void d(Map<String, Object> metadata, Throwable t) {
+    TREE_OF_SOULS.d(metadata, t);
+  }
+
   /** Log an info message with optional format args. */
   public static void i(@NonNls String message, Object... args) {
     TREE_OF_SOULS.i(message, args);
   }
 
+  /** Log an info message with metadata and optional format args. */
+  public static void i(Map<String, Object> metaData, @NonNls String message, Object... args) {
+    TREE_OF_SOULS.i(metaData, message, args);
+  }
+
   /** Log an info exception and a message with optional format args. */
   public static void i(Throwable t, @NonNls String message, Object... args) {
     TREE_OF_SOULS.i(t, message, args);
   }
 
+  /** Log an info exception and a message with optional format args. */
+  public static void i(Throwable t, Map<String, Object> metadata,
+                       @NonNls String message, Object... args) {
+    TREE_OF_SOULS.i(t, metadata, message, args);
+  }
+
   /** Log an info exception. */
   public static void i(Throwable t) {
     TREE_OF_SOULS.i(t);
   }
 
+  /** Log an info exception with metadata. */
+  public static void i(Map<String, Object> metadata, Throwable t) {
+    TREE_OF_SOULS.i(metadata, t);
+  }
+
   /** Log a warning message with optional format args. */
   public static void w(@NonNls String message, Object... args) {
     TREE_OF_SOULS.w(message, args);
   }
 
+  /** Log a warning message with metadata and optional format args. */
+  public static void w(Map<String, Object> metaData, @NonNls String message, Object... args) {
+    TREE_OF_SOULS.w(metaData, message, args);
+  }
+
   /** Log a warning exception and a message with optional format args. */
   public static void w(Throwable t, @NonNls String message, Object... args) {
     TREE_OF_SOULS.w(t, message, args);
   }
 
+  /** Log a verbose exception and a message with optional format args. */
+  public static void w(Throwable t, Map<String, Object> metadata,
+                       @NonNls String message, Object... args) {
+    TREE_OF_SOULS.w(t, metadata, message, args);
+  }
+
   /** Log a warning exception. */
   public static void w(Throwable t) {
     TREE_OF_SOULS.w(t);
   }
 
+  /** Log a warning exception with metadata. */
+  public static void w(Map<String, Object> metadata, Throwable t) {
+    TREE_OF_SOULS.w(metadata, t);
+  }
+
   /** Log an error message with optional format args. */
   public static void e(@NonNls String message, Object... args) {
     TREE_OF_SOULS.e(message, args);
   }
 
+  /** Log an error message with metadata and optional format args. */
+  public static void e(Map<String, Object> metaData, @NonNls String message, Object... args) {
+    TREE_OF_SOULS.e(metaData, message, args);
+  }
+
   /** Log an error exception and a message with optional format args. */
   public static void e(Throwable t, @NonNls String message, Object... args) {
     TREE_OF_SOULS.e(t, message, args);
   }
 
+  /** Log an error exception and a message with optional format args. */
+  public static void e(Throwable t, Map<String, Object> metadata, @NonNls String message,
+                       Object... args) {
+    TREE_OF_SOULS.e(t, metadata, message, args);
+  }
+
   /** Log an error exception. */
   public static void e(Throwable t) {
     TREE_OF_SOULS.e(t);
   }
 
+  /** Log an error exception with metadata. */
+  public static void e(Map<String, Object> metadata, Throwable t) {
+    TREE_OF_SOULS.e(metadata, t);
+  }
+
   /** Log an assert message with optional format args. */
   public static void wtf(@NonNls String message, Object... args) {
     TREE_OF_SOULS.wtf(message, args);
   }
 
+  /** Log an assert message with metadata and optional format args. */
+  public static void wtf(Map<String, Object> metaData, @NonNls String message, Object... args) {
+    TREE_OF_SOULS.wtf(metaData, message, args);
+  }
+
   /** Log an assert exception and a message with optional format args. */
   public static void wtf(Throwable t, @NonNls String message, Object... args) {
     TREE_OF_SOULS.wtf(t, message, args);
   }
 
+  /** Log an assert exception and a message with optional format args. */
+  public static void wtf(Throwable t, Map<String, Object> metadata, @NonNls String message,
+                         Object... args) {
+    TREE_OF_SOULS.wtf(t, metadata, message, args);
+  }
+
   /** Log an assert exception. */
   public static void wtf(Throwable t) {
     TREE_OF_SOULS.wtf(t);
   }
 
+  /** Log an assert exception with metadata. */
+  public static void wtf(Map<String, Object> metadata, Throwable t) {
+    TREE_OF_SOULS.wtf(metadata, t);
+  }
+
   /** Log at {@code priority} a message with optional format args. */
   public static void log(int priority, @NonNls String message, Object... args) {
     TREE_OF_SOULS.log(priority, message, args);
@@ -225,6 +321,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void v(Map<String, Object> metadata, String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].v(metadata, message, args);
+      }
+    }
+
     @Override public void v(Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -233,6 +337,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void v(Throwable t, Map<String, Object> metadata,
+                            String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].v(t, metadata, message, args);
+      }
+    }
+
     @Override public void v(Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -241,6 +354,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void v(Map<String, Object> metadata, Throwable t) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].v(metadata, t);
+      }
+    }
+
     @Override public void d(String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -249,6 +370,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void d(Map<String, Object> metadata, String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].d(metadata, message, args);
+      }
+    }
+
     @Override public void d(Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -257,6 +386,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void d(Throwable t, Map<String, Object> metadata,
+                            String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].d(t, metadata, message, args);
+      }
+    }
+
     @Override public void d(Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -265,6 +403,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void d(Map<String, Object> metadata, Throwable t) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].d(metadata, t);
+      }
+    }
+
     @Override public void i(String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -273,6 +419,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void i(Map<String, Object> metadata, String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].i(metadata, message, args);
+      }
+    }
+
     @Override public void i(Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -281,6 +435,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void i(Throwable t, Map<String, Object> metadata,
+                            String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].i(t, metadata, message, args);
+      }
+    }
+
     @Override public void i(Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -289,6 +452,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void i(Map<String, Object> metadata, Throwable t) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].i(metadata, t);
+      }
+    }
+
     @Override public void w(String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -297,6 +468,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void w(Map<String, Object> metadata, String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].w(metadata, message, args);
+      }
+    }
+
     @Override public void w(Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -305,6 +484,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void w(Throwable t, Map<String, Object> metadata, String message,
+                            Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].w(t, metadata, message, args);
+      }
+    }
+
     @Override public void w(Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -313,6 +501,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void w(Map<String, Object> metadata, Throwable t) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].w(metadata, t);
+      }
+    }
+
     @Override public void e(String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -321,6 +517,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void e(Map<String, Object> metadata, String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].e(metadata, message, args);
+      }
+    }
+
     @Override public void e(Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -329,6 +533,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void e(Throwable t, Map<String, Object> metadata, String message,
+                            Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].e(t, metadata, message, args);
+      }
+    }
+
     @Override public void e(Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -337,6 +550,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void e(Map<String, Object> metadata, Throwable t) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].e(metadata, t);
+      }
+    }
+
     @Override public void wtf(String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -345,6 +566,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void wtf(Map<String, Object> metadata, String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].wtf(metadata, message, args);
+      }
+    }
+
     @Override public void wtf(Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -353,6 +582,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void wtf(Throwable t, Map<String, Object> metadata, String message,
+                              Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].wtf(t, metadata, message, args);
+      }
+    }
+
     @Override public void wtf(Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -361,6 +599,14 @@ public static int treeCount() {
       }
     }
 
+    @Override public void wtf(Map<String, Object> metadata, Throwable t) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].wtf(metadata, t);
+      }
+    }
+
     @Override public void log(int priority, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -369,6 +615,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void log(int priority, Map<String, Object> metadata,
+                    String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].log(priority, metadata, message, args);
+      }
+    }
+
     @Override public void log(int priority, Throwable t, String message, Object... args) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -377,6 +632,15 @@ public static int treeCount() {
       }
     }
 
+    @Override public void log(int priority, Throwable t, Map<String, Object> metadata,
+                              String message, Object... args) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].log(priority, t, metadata, message, args);
+      }
+    }
+
     @Override public void log(int priority, Throwable t) {
       Tree[] forest = forestAsArray;
       //noinspection ForLoopReplaceableByForEach
@@ -385,6 +649,19 @@ public static int treeCount() {
       }
     }
 
+    @Override public void log(int priority, Throwable t, Map<String, Object> metadata) {
+      Tree[] forest = forestAsArray;
+      //noinspection ForLoopReplaceableByForEach
+      for (int i = 0, count = forest.length; i < count; i++) {
+        forest[i].log(priority, t, metadata);
+      }
+    }
+
+    @Override protected void log(int priority, String tag, @NotNull String message, Throwable t,
+                                 Map<String, Object> metadata) {
+      throw new AssertionError("Missing override for log method. test test");
+    }
+
     @Override protected void log(int priority, String tag, @NotNull String message, Throwable t) {
       throw new AssertionError("Missing override for log method.");
     }
@@ -409,107 +686,213 @@ String getTag() {
 
     /** Log a verbose message with optional format args. */
     public void v(String message, Object... args) {
-      prepareLog(Log.VERBOSE, null, message, args);
+      prepareLog(Log.VERBOSE, null, null, message, args);
+    }
+
+    /** Log a verbose message with metadata and optional format args. */
+    public void v(Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.VERBOSE, null, metadata, message, args);
     }
 
     /** Log a verbose exception and a message with optional format args. */
     public void v(Throwable t, String message, Object... args) {
-      prepareLog(Log.VERBOSE, t, message, args);
+      prepareLog(Log.VERBOSE, t, null, message, args);
+    }
+
+    /** Log a verbose exception with metadata and a message with optional format args. */
+    public void v(Throwable t, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.VERBOSE, t, metadata, message, args);
     }
 
     /** Log a verbose exception. */
     public void v(Throwable t) {
-      prepareLog(Log.VERBOSE, t, null);
+      prepareLog(Log.VERBOSE, t, null, null);
+    }
+
+    /** Log a verbose exception with metadata. */
+    public void v(Map<String, Object> metadata, Throwable t) {
+      prepareLog(Log.VERBOSE, t, metadata, null);
     }
 
     /** Log a debug message with optional format args. */
     public void d(String message, Object... args) {
-      prepareLog(Log.DEBUG, null, message, args);
+      prepareLog(Log.DEBUG, null, null, message, args);
+    }
+
+    /** Log a debug message with metadata and optional format args. */
+    public void d(Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.DEBUG, null, metadata, message, args);
     }
 
     /** Log a debug exception and a message with optional format args. */
     public void d(Throwable t, String message, Object... args) {
-      prepareLog(Log.DEBUG, t, message, args);
+      prepareLog(Log.DEBUG, t, null, message, args);
+    }
+
+    /** Log a debug exception with metadata and a message with optional format args. */
+    public void d(Throwable t, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.DEBUG, t, metadata, message, args);
     }
 
     /** Log a debug exception. */
     public void d(Throwable t) {
-      prepareLog(Log.DEBUG, t, null);
+      prepareLog(Log.DEBUG, t, null, null);
+    }
+
+    /** Log a verbose exception with metadata. */
+    public void d(Map<String, Object> metadata, Throwable t) {
+      prepareLog(Log.DEBUG, t, metadata, null);
     }
 
     /** Log an info message with optional format args. */
     public void i(String message, Object... args) {
-      prepareLog(Log.INFO, null, message, args);
+      prepareLog(Log.INFO, null, null, message, args);
+    }
+
+    /** Log an info message with metadata and optional format args. */
+    public void i(Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.INFO, null, metadata, message, args);
     }
 
     /** Log an info exception and a message with optional format args. */
     public void i(Throwable t, String message, Object... args) {
-      prepareLog(Log.INFO, t, message, args);
+      prepareLog(Log.INFO, t, null, message, args);
+    }
+
+    /** Log an info exception with metadata and a message with optional format args. */
+    public void i(Throwable t, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.INFO, t, metadata, message, args);
     }
 
     /** Log an info exception. */
     public void i(Throwable t) {
-      prepareLog(Log.INFO, t, null);
+      prepareLog(Log.INFO, t, null, null);
+    }
+
+    /** Log an info exception with metadata. */
+    public void i(Map<String, Object> metadata, Throwable t) {
+      prepareLog(Log.INFO, t, metadata, null);
     }
 
     /** Log a warning message with optional format args. */
     public void w(String message, Object... args) {
-      prepareLog(Log.WARN, null, message, args);
+      prepareLog(Log.WARN, null, null, message, args);
+    }
+
+    /** Log a warning message with metadata and optional format args. */
+    public void w(Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.WARN, null, metadata, message, args);
     }
 
     /** Log a warning exception and a message with optional format args. */
     public void w(Throwable t, String message, Object... args) {
-      prepareLog(Log.WARN, t, message, args);
+      prepareLog(Log.WARN, t, null, message, args);
+    }
+
+    /** Log a warning exception with metadata and a message with optional format args. */
+    public void w(Throwable t, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.WARN, t, metadata, message, args);
     }
 
     /** Log a warning exception. */
     public void w(Throwable t) {
-      prepareLog(Log.WARN, t, null);
+      prepareLog(Log.WARN, t, null, null);
+    }
+
+    /** Log a warning exception with metadata. */
+    public void w(Map<String, Object> metadata, Throwable t) {
+      prepareLog(Log.WARN, t, metadata, null);
     }
 
     /** Log an error message with optional format args. */
     public void e(String message, Object... args) {
-      prepareLog(Log.ERROR, null, message, args);
+      prepareLog(Log.ERROR, null, null, message, args);
+    }
+
+    /** Log an error message with metadata and optional format args. */
+    public void e(Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.ERROR, null, metadata, message, args);
     }
 
     /** Log an error exception and a message with optional format args. */
     public void e(Throwable t, String message, Object... args) {
-      prepareLog(Log.ERROR, t, message, args);
+      prepareLog(Log.ERROR, t, null, message, args);
+    }
+
+    /** Log an error exception with metadata and a message with optional format args. */
+    public void e(Throwable t, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.ERROR, t, metadata, message, args);
     }
 
     /** Log an error exception. */
     public void e(Throwable t) {
-      prepareLog(Log.ERROR, t, null);
+      prepareLog(Log.ERROR, t, null, null);
+    }
+
+    /** Log an error exception with metadata. */
+    public void e(Map<String, Object> metadata, Throwable t) {
+      prepareLog(Log.ERROR, t, metadata, null);
     }
 
     /** Log an assert message with optional format args. */
     public void wtf(String message, Object... args) {
-      prepareLog(Log.ASSERT, null, message, args);
+      prepareLog(Log.ASSERT, null, null, message, args);
+    }
+
+    /** Log a verbose message with metadata and optional format args. */
+    public void wtf(Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.VERBOSE, null, metadata, message, args);
     }
 
     /** Log an assert exception and a message with optional format args. */
     public void wtf(Throwable t, String message, Object... args) {
-      prepareLog(Log.ASSERT, t, message, args);
+      prepareLog(Log.ASSERT, t, null, message, args);
+    }
+
+    /** Log a verbose exception with metadata and a message with optional format args. */
+    public void wtf(Throwable t, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(Log.VERBOSE, t, metadata, message, args);
     }
 
     /** Log an assert exception. */
     public void wtf(Throwable t) {
-      prepareLog(Log.ASSERT, t, null);
+      prepareLog(Log.ASSERT, t, null, null);
+    }
+
+    /** Log a verbose exception with metadata. */
+    public void wtf(Map<String, Object> metadata, Throwable t) {
+      prepareLog(Log.VERBOSE, t, metadata, null);
     }
 
     /** Log at {@code priority} a message with optional format args. */
     public void log(int priority, String message, Object... args) {
-      prepareLog(priority, null, message, args);
+      prepareLog(priority, null, null, message, args);
+    }
+
+    /** Log at {@code priority} metadata and a message with optional format args. */
+    public void log(int priority, Map<String, Object> metadata, String message, Object... args) {
+      prepareLog(priority, null, metadata,  message, args);
     }
 
     /** Log at {@code priority} an exception and a message with optional format args. */
     public void log(int priority, Throwable t, String message, Object... args) {
-      prepareLog(priority, t, message, args);
+      prepareLog(priority, t, null, message, args);
+    }
+
+    /** Log at {@code priority} an exception, metadata and a message with optional format args. */
+    public void log(int priority, Throwable t, Map<String, Object> metadata,
+                    String message, Object... args) {
+      prepareLog(priority, t, metadata, message, args);
     }
 
     /** Log at {@code priority} an exception. */
     public void log(int priority, Throwable t) {
-      prepareLog(priority, t, null);
+      prepareLog(priority, t, null, null);
+    }
+
+    /** Log at {@code priority} an exception and metadata. */
+    public void log(int priority, Throwable t, Map<String, Object> metadata) {
+      prepareLog(priority, t, metadata, null);
     }
 
     /**
@@ -527,7 +910,8 @@ protected boolean isLoggable(@Nullable String tag, int priority) {
       return isLoggable(priority);
     }
 
-    private void prepareLog(int priority, Throwable t, String message, Object... args) {
+    private void prepareLog(int priority, Throwable t, Map<String, Object> metadata,
+                            String message, Object... args) {
       // Consume tag even when message is not loggable so that next message is correctly tagged.
       String tag = getTag();
 
@@ -551,7 +935,11 @@ private void prepareLog(int priority, Throwable t, String message, Object... arg
         }
       }
 
-      log(priority, tag, message, t);
+      if (metadata == null) {
+        log(priority, tag, message, t);
+      } else {
+        log(priority, tag, message, t, metadata);
+      }
     }
 
     /**
@@ -571,6 +959,20 @@ private String getStackTraceString(Throwable t) {
       return sw.toString();
     }
 
+    /**
+     * Write a log message to its destination. This must be overridden in order to capture metadata.
+     *
+     * @param priority Log level. See {@link Log} for constants.
+     * @param tag Explicit or inferred tag. May be {@code null}.
+     * @param message Formatted log message. May be {@code null}, but then {@code t} will not be.
+     * @param t Accompanying exceptions. May be {@code null}, but then {@code message} will not be.
+     * @param metadata metadata associated with the log statement. May be {@code null}.
+     */
+    protected void log(int priority, @Nullable String tag, @NotNull String message,
+                                @Nullable Throwable t, @Nullable Map<String, Object> metadata) {
+      throw new IllegalArgumentException("You must override this method to log with metadata");
+    }
+
     /**
      * Write a log message to its destination. Called for all level-specific methods by default.
      *
diff --git a/timber/src/test/java/timber/log/TimberTest.java b/timber/src/test/java/timber/log/TimberTest.java
index df509f281..a3aa3badd 100644
--- a/timber/src/test/java/timber/log/TimberTest.java
+++ b/timber/src/test/java/timber/log/TimberTest.java
@@ -6,7 +6,9 @@
 import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.CountDownLatch;
 import org.jetbrains.annotations.NotNull;
 import org.junit.After;
@@ -41,7 +43,7 @@ public class TimberTest {
     Timber.d("Test");
 
     assertLog()
-        .hasDebugMessage("TimberTest:41", "Test")
+        .hasDebugMessage("TimberTest:43", "Test")
         .hasNoMoreMessages();
   }
 
@@ -510,6 +512,31 @@ protected String formatMessage(@NotNull String message, @NotNull Object[] args)
         .hasNoMoreMessages();
   }
 
+  @Test public void loggingMetadataFailsWhenNotImplemented() {
+    Timber.plant(new Timber.DebugTree());
+    try {
+      Timber.d(new HashMap<String, Object>(), "TimberTest");
+    } catch (IllegalArgumentException e) {
+      assertThat(e).hasMessageThat().startsWith("You must override this method to log with metadata");
+    }
+  }
+
+  @Test public void loggingMetadataWorksWhenImplemented() {
+    final String key = "test-key";
+    final String value = "test-content";
+    Timber.Tree testTree = new Timber.DebugTree() {
+      @Override protected void log(int priority, String tag, @NotNull String message, Throwable t,
+                                   Map<String, Object> metadata) {
+        Object result = metadata.get(key);
+        assertThat(result).isEqualTo(value);
+      }
+    };
+    Timber.plant(testTree);
+    Map<String, Object> metadata = new HashMap<>();
+    metadata.put(key, value);
+    Timber.d(metadata, "TimberTest");
+  }
+
   private static <T extends Throwable> T truncatedThrowable(Class<T> throwableClass) {
     try {
       T throwable = throwableClass.newInstance();