diff --git a/lib/pact_broker/api/decorators/matrix_decorator.rb b/lib/pact_broker/api/decorators/matrix_decorator.rb
index 94b0f8aad..d53182d88 100644
--- a/lib/pact_broker/api/decorators/matrix_decorator.rb
+++ b/lib/pact_broker/api/decorators/matrix_decorator.rb
@@ -17,6 +17,9 @@ def to_json(options)
 
         def to_hash(options)
           {
+            summary: {
+              compatible: compatible?
+            },
             matrix: matrix(lines, options[:user_options][:base_url])
           }
         end
@@ -25,6 +28,10 @@ def to_hash(options)
 
         attr_reader :lines
 
+        def compatible?
+          lines.any? && lines.all?{ |line| line[:success] }
+        end
+
         def matrix(lines, base_url)
           provider = nil
           consumer = nil
diff --git a/lib/pact_broker/api/resources/matrix.rb b/lib/pact_broker/api/resources/matrix.rb
index 1f1956c0c..ca0c48c49 100644
--- a/lib/pact_broker/api/resources/matrix.rb
+++ b/lib/pact_broker/api/resources/matrix.rb
@@ -27,7 +27,7 @@ def malformed_request?
 
         def to_json
           criteria = selected_versions.each_with_object({}) { | version, hash | hash[version.pacticipant.name] = version.number }
-          lines = matrix_service.find_compatible_pacticipant_versions(criteria)
+          lines = matrix_service.find(criteria)
           PactBroker::Api::Decorators::MatrixPactDecorator.new(lines).to_json(user_options: { base_url: base_url })
         end
 
diff --git a/lib/pact_broker/matrix/service.rb b/lib/pact_broker/matrix/service.rb
index f8a15597c..f95dab487 100644
--- a/lib/pact_broker/matrix/service.rb
+++ b/lib/pact_broker/matrix/service.rb
@@ -9,6 +9,10 @@ module Service
       extend PactBroker::Repositories
       extend PactBroker::Services
 
+      def find criteria
+        matrix_repository.find criteria
+      end
+
       def find_for_consumer_and_provider params
         matrix_repository.find_for_consumer_and_provider params[:consumer_name], params[:provider_name]
       end
@@ -43,6 +47,10 @@ def validate_selectors selectors
           end
         end
 
+        if selectors.size < 2
+          error_messages << "Please provide 2 or more version selectors."
+        end
+
         error_messages
       end
     end
diff --git a/spec/lib/pact_broker/api/decorators/matrix_decorator_spec.rb b/spec/lib/pact_broker/api/decorators/matrix_decorator_spec.rb
index 24e9d8621..9a8d9f1f3 100644
--- a/spec/lib/pact_broker/api/decorators/matrix_decorator_spec.rb
+++ b/spec/lib/pact_broker/api/decorators/matrix_decorator_spec.rb
@@ -113,6 +113,10 @@ module Decorators
             expect(parsed_json[:matrix][0][:pact]).to eq pact_hash
           end
 
+          it "includes a summary" do
+            expect(parsed_json[:summary][:compatible]).to eq false
+          end
+
           context "when the pact has not been verified" do
             let(:verification_hash) do
               nil
diff --git a/spec/lib/pact_broker/matrix/service_spec.rb b/spec/lib/pact_broker/matrix/service_spec.rb
index 3d9c0e4bf..23bfa220e 100644
--- a/spec/lib/pact_broker/matrix/service_spec.rb
+++ b/spec/lib/pact_broker/matrix/service_spec.rb
@@ -3,8 +3,9 @@
 module PactBroker
   module Matrix
     describe Service do
+      let(:td) { TestDataBuilder.new }
+
       describe "validate_selectors" do
-        let(:td) { TestDataBuilder.new }
 
         subject { Service.validate_selectors(selectors) }
 
@@ -16,6 +17,19 @@ module Matrix
           end
         end
 
+        context "when there is only one selector" do
+          before do
+            td.create_pacticipant("Foo")
+              .create_version("1")
+          end
+
+          let(:selectors) { ["Foo/version/1"] }
+
+          it "returns error messages" do
+            expect(subject.first).to eq "Please provide 2 or more version selectors."
+          end
+        end
+
         context "when one or more of the selectors does not match any known version" do
           before do
             td.create_pacticipant("Foo")