diff --git a/README.md b/README.md
index ac80da3..13e4876 100644
--- a/README.md
+++ b/README.md
@@ -106,6 +106,16 @@ user = User.first
 user = User.find_by(email: "alice@example.com")
 user = User.find_by!(email: "alice@example.com") # raises if not found
 
+# find or create
+user = User.find_or_create_by(email: "alice@example.com") # finds or creates
+user = User.find_or_create_by!(email: "alice@example.com") # raises on validation error
+
+# find or create with a block (block only runs if creating)
+user = User.find_or_create_by(email: "alice@example.com") do |u|
+  u.first_name = "Alice"
+  u.last_name = "Smith"
+end
+
 # update
 user.update(first_name: "Alicia")
 user.first_name = "Alicia"
diff --git a/lib/airctiverecord/base.rb b/lib/airctiverecord/base.rb
index 1934561..694d225 100644
--- a/lib/airctiverecord/base.rb
+++ b/lib/airctiverecord/base.rb
@@ -28,6 +28,20 @@ def relation_class
       end
 
       def relation_class_name = "#{name}::Relation"
+
+      def create(attributes = {}, &block)
+        record = new(attributes)
+        yield(record) if block_given?
+        record.save
+        record
+      end
+
+      def create!(attributes = {}, &block)
+        record = new(attributes)
+        yield(record) if block_given?
+        record.save!
+        record
+      end
     end
 
     def initialize(attributes = {}, **kwargs)
diff --git a/lib/airctiverecord/scoping.rb b/lib/airctiverecord/scoping.rb
index ae7634b..a053f2a 100644
--- a/lib/airctiverecord/scoping.rb
+++ b/lib/airctiverecord/scoping.rb
@@ -36,6 +36,14 @@ def find_by(conditions) = all.find_by(conditions)
 
       def find_by!(conditions) = all.find_by!(conditions)
 
+      def find_or_create_by(conditions, &block)
+        find_by(conditions) || create(conditions, &block)
+      end
+
+      def find_or_create_by!(conditions, &block)
+        find_by(conditions) || create!(conditions, &block)
+      end
+
       def first(limit = nil) = all.first(limit)
 
       def last(limit = nil) = all.last(limit)
diff --git a/lib/airctiverecord/version.rb b/lib/airctiverecord/version.rb
index 8800d5f..34c6b29 100644
--- a/lib/airctiverecord/version.rb
+++ b/lib/airctiverecord/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module AirctiveRecord
-  VERSION = "0.2.1"
+  VERSION = "0.3.0"
 end
diff --git a/spec/find_or_create_by_spec.rb b/spec/find_or_create_by_spec.rb
new file mode 100644
index 0000000..3032e07
--- /dev/null
+++ b/spec/find_or_create_by_spec.rb
@@ -0,0 +1,239 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+
+RSpec.describe "find_or_create_by" do
+  let(:model_class) do
+    build_test_model("TestUser") do
+      self.base_key = "appTest123"
+      self.table_name = "Users"
+
+      field :email, "Email Address"
+      field :name, "Name"
+      field :age, "Age"
+
+      validates :email, presence: true
+      validates :age, numericality: { greater_than: 0 }, allow_nil: true
+
+      def self.records(**params)
+        @last_params = params
+        @stub_records || []
+      end
+
+      class << self
+        attr_reader :last_params
+        attr_accessor :stub_records
+      end
+    end
+  end
+
+  before do
+    model_class.stub_records = []
+  end
+
+  describe "#find_or_create_by" do
+    context "when record exists" do
+      it "returns the existing record" do
+        existing_record = model_class.new(email: "test@example.com", name: "Alice")
+        existing_record.instance_variable_set(:@id, "rec123")
+        existing_record.instance_variable_set(:@new_record, false)
+        
+        model_class.stub_records = [existing_record]
+
+        result = model_class.find_or_create_by(email: "test@example.com")
+
+        expect(result).to eq(existing_record)
+        expect(result.id).to eq("rec123")
+      end
+    end
+
+    context "when record does not exist" do
+      it "creates a new record" do
+        # Mock save to return true and set id
+        allow_any_instance_of(model_class).to receive(:save) do |record|
+          record.instance_variable_set(:@id, "rec#{rand(100000)}")
+          record.instance_variable_set(:@new_record, false)
+          true
+        end
+
+        result = model_class.find_or_create_by(email: "new@example.com", name: "Bob")
+
+        expect(result).to be_a(model_class)
+        expect(result.email).to eq("new@example.com")
+        expect(result.name).to eq("Bob")
+        expect(result.id).to be_present
+      end
+
+      it "returns the created record even if invalid" do
+        result = model_class.find_or_create_by(email: nil, name: "Invalid")
+
+        expect(result).to be_a(model_class)
+        expect(result.valid?).to be false
+        expect(result.new_record?).to be true
+      end
+    end
+
+    context "with field mappings" do
+      it "uses field mappings in both find and create" do
+        # Mock save to return true and set id
+        allow_any_instance_of(model_class).to receive(:save) do |record|
+          record.instance_variable_set(:@id, "rec#{rand(100000)}")
+          record.instance_variable_set(:@new_record, false)
+          true
+        end
+
+        result = model_class.find_or_create_by(email: "mapped@example.com", name: "Charlie")
+
+        # Check that the find_by was called with conditions
+        expect(model_class.last_params[:filter]).to include("{Email Address} = 'mapped@example.com'")
+        
+        # Check record was created with mapped fields
+        expect(result.email).to eq("mapped@example.com")
+        expect(result.name).to eq("Charlie")
+      end
+    end
+
+    context "with a block" do
+      it "yields to the block when creating a new record" do
+        # Mock save to return true and set id
+        allow_any_instance_of(model_class).to receive(:save) do |record|
+          record.instance_variable_set(:@id, "rec#{rand(100000)}")
+          record.instance_variable_set(:@new_record, false)
+          true
+        end
+
+        result = model_class.find_or_create_by(email: "block@example.com") do |user|
+          user.name = "Block User"
+          user.age = 25
+        end
+
+        expect(result.email).to eq("block@example.com")
+        expect(result.name).to eq("Block User")
+        expect(result.age).to eq(25)
+      end
+
+      it "does not yield when record exists" do
+        existing_record = model_class.new(email: "exists@example.com", name: "Existing")
+        existing_record.instance_variable_set(:@id, "rec789")
+        existing_record.instance_variable_set(:@new_record, false)
+        
+        model_class.stub_records = [existing_record]
+
+        block_called = false
+        result = model_class.find_or_create_by(email: "exists@example.com") do |user|
+          block_called = true
+          user.name = "Should Not Change"
+        end
+
+        expect(block_called).to be false
+        expect(result.name).to eq("Existing")
+      end
+    end
+  end
+
+  describe "#find_or_create_by!" do
+    context "when record exists" do
+      it "returns the existing record" do
+        existing_record = model_class.new(email: "test@example.com", name: "Alice")
+        existing_record.instance_variable_set(:@id, "rec456")
+        existing_record.instance_variable_set(:@new_record, false)
+        
+        model_class.stub_records = [existing_record]
+
+        result = model_class.find_or_create_by!(email: "test@example.com")
+
+        expect(result).to eq(existing_record)
+        expect(result.id).to eq("rec456")
+      end
+    end
+
+    context "when record does not exist" do
+      it "creates a new record" do
+        # Mock save! to return true and set id
+        allow_any_instance_of(model_class).to receive(:save!) do |record|
+          record.instance_variable_set(:@id, "rec#{rand(100000)}")
+          record.instance_variable_set(:@new_record, false)
+          true
+        end
+
+        result = model_class.find_or_create_by!(email: "new@example.com", name: "Bob")
+
+        expect(result).to be_a(model_class)
+        expect(result.email).to eq("new@example.com")
+        expect(result.name).to eq("Bob")
+        expect(result.id).to be_present
+      end
+
+      it "raises RecordInvalid if validation fails" do
+        expect do
+          model_class.find_or_create_by!(email: nil, name: "Invalid")
+        end.to raise_error(AirctiveRecord::RecordInvalid, /can't be blank/)
+      end
+    end
+
+    context "with field mappings" do
+      it "uses field mappings in both find and create" do
+        # Mock save! to return true and set id
+        allow_any_instance_of(model_class).to receive(:save!) do |record|
+          record.instance_variable_set(:@id, "rec#{rand(100000)}")
+          record.instance_variable_set(:@new_record, false)
+          true
+        end
+
+        result = model_class.find_or_create_by!(email: "mapped2@example.com", name: "Diana")
+
+        # Check that the find_by was called with conditions
+        expect(model_class.last_params[:filter]).to include("{Email Address} = 'mapped2@example.com'")
+        
+        # Check record was created with mapped fields
+        expect(result.email).to eq("mapped2@example.com")
+        expect(result.name).to eq("Diana")
+      end
+    end
+
+    context "with a block" do
+      it "yields to the block when creating a new record" do
+        # Mock save! to return true and set id
+        allow_any_instance_of(model_class).to receive(:save!) do |record|
+          record.instance_variable_set(:@id, "rec#{rand(100000)}")
+          record.instance_variable_set(:@new_record, false)
+          true
+        end
+
+        result = model_class.find_or_create_by!(email: "block@example.com") do |user|
+          user.name = "Block User"
+          user.age = 30
+        end
+
+        expect(result.email).to eq("block@example.com")
+        expect(result.name).to eq("Block User")
+        expect(result.age).to eq(30)
+      end
+
+      it "does not yield when record exists" do
+        existing_record = model_class.new(email: "exists@example.com", name: "Existing")
+        existing_record.instance_variable_set(:@id, "rec999")
+        existing_record.instance_variable_set(:@new_record, false)
+        
+        model_class.stub_records = [existing_record]
+
+        block_called = false
+        result = model_class.find_or_create_by!(email: "exists@example.com") do |user|
+          block_called = true
+          user.name = "Should Not Change"
+        end
+
+        expect(block_called).to be false
+        expect(result.name).to eq("Existing")
+      end
+
+      it "raises RecordInvalid with block attributes if validation fails" do
+        expect do
+          model_class.find_or_create_by!(email: "invalid@example.com") do |user|
+            user.email = nil # Make it invalid
+          end
+        end.to raise_error(AirctiveRecord::RecordInvalid, /can't be blank/)
+      end
+    end
+  end
+end