diff --git a/CHANGELOG.md b/CHANGELOG.md
index 28d5830..b4e0b3f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 #### Features
 
-* Your contribution here.
+* [#33](https://github.com/ruby-grape/grape-swagger-entity/pull/33): Update parser to respect merge option for entities - [@b-boogaard](https://github.com/b-boogaard).
 
 #### Fixes
 
diff --git a/lib/grape-swagger/entity/parser.rb b/lib/grape-swagger/entity/parser.rb
index 105cdc5..7527110 100644
--- a/lib/grape-swagger/entity/parser.rb
+++ b/lib/grape-swagger/entity/parser.rb
@@ -12,15 +12,23 @@ def initialize(model, endpoint)
       end
 
       def call
-        parameters = model.root_exposures.each_with_object({}) do |value, memo|
-          memo[value.attribute] = value.send(:options)
-        end
-
-        parse_grape_entity_params(parameters)
+        parse_grape_entity_params(extract_params(model))
       end
 
       private
 
+      def extract_params(exposure)
+        exposure.root_exposures.each_with_object({}) do |value, memo|
+          if value.for_merge && (value.respond_to?(:entity_class) || value.respond_to?(:using_class_name))
+            entity_class = value.respond_to?(:entity_class) ? value.entity_class : value.using_class_name
+
+            memo.merge!(extract_params(entity_class))
+          else
+            memo[value.attribute] = value.send(:options)
+          end
+        end
+      end
+
       def parse_grape_entity_params(params, parent_model = nil)
         return unless params
 
diff --git a/spec/grape-swagger/entities/response_model_spec.rb b/spec/grape-swagger/entities/response_model_spec.rb
index b9c9b63..ef4c24d 100644
--- a/spec/grape-swagger/entities/response_model_spec.rb
+++ b/spec/grape-swagger/entities/response_model_spec.rb
@@ -56,7 +56,10 @@ def app
             'kind2' => { '$ref' => '#/definitions/Kind', 'description' => 'Secondary kind.' },
             'kind3' => { '$ref' => '#/definitions/Kind', 'description' => 'Tertiary kind.' },
             'tags' => { 'type' => 'array', 'items' => { '$ref' => '#/definitions/Tag' }, 'description' => 'Tags.' },
-            'relation' => { '$ref' => '#/definitions/Relation', 'description' => 'A related model.' } }
+            'relation' => { '$ref' => '#/definitions/Relation', 'description' => 'A related model.' },
+            'code' => { 'type' => 'string', 'description' => 'Error code' },
+            'message' => { 'type' => 'string', 'description' => 'Error message' },
+            'attr' => { 'type' => 'string', 'description' => 'Attribute' } }
     )
 
     expect(subject['definitions'].keys).to include 'Kind'
@@ -134,6 +137,7 @@ class SomeEntity < Grape::Entity
           expose :relation, using: TheseApi::Entities::Relation, documentation: { type: 'TheseApi::Relation', desc: 'A related model.' }
           expose :values, using: TheseApi::Entities::Values, documentation: { desc: 'Tertiary kind.' }
           expose :nested, using: TheseApi::Entities::Nested, documentation: { desc: 'Nested object.' }
+          expose :merged_attribute, using: ThisApi::Entities::Nested, merge: true
         end
       end
 
@@ -246,7 +250,10 @@ def app
         'tags' => { 'type' => 'array', 'items' => { '$ref' => '#/definitions/Tag' }, 'description' => 'Tags.' },
         'relation' => { '$ref' => '#/definitions/Relation', 'description' => 'A related model.' },
         'values' => { '$ref' => '#/definitions/Values', 'description' => 'Tertiary kind.' },
-        'nested' => { '$ref' => '#/definitions/Nested', 'description' => 'Nested object.' }
+        'nested' => { '$ref' => '#/definitions/Nested', 'description' => 'Nested object.' },
+        'code' => { 'type' => 'string', 'description' => 'Error code' },
+        'message' => { 'type' => 'string', 'description' => 'Error message' },
+        'attr' => { 'type' => 'string', 'description' => 'Attribute' }
       },
       'description' => 'This returns something'
     )
diff --git a/spec/grape-swagger/entity/parser_spec.rb b/spec/grape-swagger/entity/parser_spec.rb
index 86e6b53..814cd3b 100644
--- a/spec/grape-swagger/entity/parser_spec.rb
+++ b/spec/grape-swagger/entity/parser_spec.rb
@@ -15,6 +15,13 @@
         expect(parsed_entity[:kind2]['$ref']).to eq('#/definitions/Kind')
         expect(parsed_entity[:kind3]['$ref']).to eq('#/definitions/Kind')
       end
+
+      it 'merges attributes that have merge: true defined' do
+        expect(parsed_entity[:merged_attribute]).to be_nil
+        expect(parsed_entity[:code][:type]).to eq('string')
+        expect(parsed_entity[:message][:type]).to eq('string')
+        expect(parsed_entity[:attr][:type]).to eq('string')
+      end
     end
   end
 end
diff --git a/spec/support/shared_contexts/this_api.rb b/spec/support/shared_contexts/this_api.rb
index fd726b5..cc7035d 100644
--- a/spec/support/shared_contexts/this_api.rb
+++ b/spec/support/shared_contexts/this_api.rb
@@ -17,6 +17,11 @@ class Error < Grape::Entity
           expose :message, documentation: { type: 'string', desc: 'Error message' }
         end
 
+        class Nested < Grape::Entity
+          expose :attr, documentation: { type: 'string', desc: 'Attribute' }
+          expose :nested_attrs, merge: true, using: ThisApi::Entities::Error
+        end
+
         class Something < Grape::Entity
           expose :text, documentation: { type: 'string', desc: 'Content of something.' }
           expose :colors, documentation: { type: 'string', desc: 'Colors', is_array: true }
@@ -25,6 +30,7 @@ class Something < Grape::Entity
           expose :kind3, using: ThisApi::Entities::Kind, documentation: { desc: 'Tertiary kind.' }
           expose :tags, using: ThisApi::Entities::Tag, documentation: { desc: 'Tags.', is_array: true }
           expose :relation, using: ThisApi::Entities::Relation, documentation: { type: 'ThisApi::Relation', desc: 'A related model.' }
+          expose :merged_attribute, using: ThisApi::Entities::Nested, merge: true
         end
       end