diff --git a/.rspec b/.rspec
index d632cbc..58e8efe 100644
--- a/.rspec
+++ b/.rspec
@@ -1,4 +1,2 @@
 --colour
 --require spec_helper
---require integration/spec_helper
---require unit/spec_helper
diff --git a/.rspec_integration b/.rspec_integration
deleted file mode 100644
index 58bc43e..0000000
--- a/.rspec_integration
+++ /dev/null
@@ -1,4 +0,0 @@
---colour
---require spec_helper
---require integration/spec_helper
---pattern spec/integration/**/*_spec.rb
diff --git a/.rspec_unit b/.rspec_unit
deleted file mode 100644
index 5443833..0000000
--- a/.rspec_unit
+++ /dev/null
@@ -1,4 +0,0 @@
---colour
---require spec_helper
---require unit/spec_helper
---pattern spec/unit/**/*_spec.rb
diff --git a/README.md b/README.md
index 730e35e..5bb7b17 100644
--- a/README.md
+++ b/README.md
@@ -118,6 +118,9 @@ contract = Pacto.build_from_file('/path/to/contract.json', 'http://dummyprovider
 response = Net::HTTP.get_response(URI.parse('http://dummyprovider.com')).body
 contract.validate response, body_only: true
 ```
+
+Pacto also has the ability to match a request signature to a contract that is currently in used, via ```Pacto.contract_for request_signature```
+
 ## Auto-Generated Stubs
 
 Pacto provides an API to be used in the consumer's acceptance tests. It uses a custom JSON Schema parser and generator
diff --git a/Rakefile b/Rakefile
index c375d74..9142001 100644
--- a/Rakefile
+++ b/Rakefile
@@ -18,16 +18,12 @@ Cucumber::Rake::Task.new(:journeys) do |t|
   t.cucumber_opts = 'features --format pretty'
 end
 
-if defined?(RSpec)
-  desc 'Run unit tests'
-  task :unit do
-    abort unless system('rspec --option .rspec_unit')
-  end
-
-  desc 'Run integration tests'
-  task :integration do
-    abort unless system('rspec --option .rspec_integration')
-  end
+RSpec::Core::RakeTask.new(:unit) do |t|
+  t.pattern = 'spec/unit/**/*_spec.rb'
+end
 
-  task :default => [:unit, :integration, :journeys, :rubocop, 'coveralls:push']
+RSpec::Core::RakeTask.new(:integration) do |t|
+  t.pattern = 'spec/integration/**/*_spec.rb'
 end
+
+task :default => [:unit, :integration, :journeys, :rubocop, 'coveralls:push']
diff --git a/lib/pacto.rb b/lib/pacto.rb
index 0255535..3bfa01d 100644
--- a/lib/pacto.rb
+++ b/lib/pacto.rb
@@ -12,6 +12,7 @@
 
 require 'pacto/core/contract_repository'
 require 'pacto/core/configuration'
+require 'pacto/core/callback'
 require 'pacto/logger'
 require 'pacto/exceptions/invalid_contract.rb'
 require 'pacto/extensions'
@@ -25,6 +26,7 @@
 require 'pacto/hash_merge_processor'
 require 'pacto/stubs/built_in'
 require 'pacto/meta_schema'
+require 'pacto/hooks/erb_hook'
 
 module Pacto
   class << self
@@ -34,6 +36,7 @@ def configuration
     end
 
     def clear!
+      Pacto.configuration.provider.reset!
       @configuration = nil
       unregister_all!
     end
diff --git a/lib/pacto/contract.rb b/lib/pacto/contract.rb
index e1934a5..f54e722 100644
--- a/lib/pacto/contract.rb
+++ b/lib/pacto/contract.rb
@@ -1,18 +1,26 @@
 module Pacto
   class Contract
-    def initialize(request, response)
+    attr_reader :values
+
+    def initialize(request, response, file = nil)
       @request = request
       @response = response
+      @file = file
     end
 
-    def stub!
-      Pacto.configuration.provider.stub!(@request, stub_response) unless @request.nil?
+    def stub_contract! values = {}
+      @values = values
+      @stub = Pacto.configuration.provider.stub_request!(@request, stub_response) unless @request.nil?
     end
 
     def validate(response_gotten = provider_response, opt = {})
       @response.validate(response_gotten, opt)
     end
 
+    def matches? request_signature
+      @stub.matches? request_signature unless @stub.nil?
+    end
+
     private
 
     def provider_response
@@ -22,5 +30,6 @@ def provider_response
     def stub_response
       @response.instantiate
     end
+
   end
 end
diff --git a/lib/pacto/contract_factory.rb b/lib/pacto/contract_factory.rb
index ee825d6..53c9ea2 100644
--- a/lib/pacto/contract_factory.rb
+++ b/lib/pacto/contract_factory.rb
@@ -9,7 +9,7 @@ def self.build_from_file(contract_path, host, preprocessor)
       schema.validate definition
       request = Request.new(host, definition['request'])
       response = Response.new(definition['response'])
-      Contract.new(request, response)
+      Contract.new(request, response, contract_path)
     end
 
     def self.schema
diff --git a/lib/pacto/core/callback.rb b/lib/pacto/core/callback.rb
new file mode 100644
index 0000000..8e6ef30
--- /dev/null
+++ b/lib/pacto/core/callback.rb
@@ -0,0 +1,11 @@
+module Pacto
+  class Callback
+    def initialize(&block)
+      @callback = block
+    end
+
+    def process(contracts, request_signature, response)
+      @callback.call contracts, request_signature, response
+    end
+  end
+end
diff --git a/lib/pacto/core/configuration.rb b/lib/pacto/core/configuration.rb
index 7f16cc4..137e12c 100644
--- a/lib/pacto/core/configuration.rb
+++ b/lib/pacto/core/configuration.rb
@@ -1,6 +1,7 @@
 module Pacto
   class Configuration
     attr_accessor :preprocessor, :postprocessor, :provider, :strict_matchers, :contracts_path, :logger
+    attr_reader :callback
 
     def initialize
       @preprocessor = ERBProcessor.new
@@ -10,10 +11,20 @@ def initialize
       @contracts_path = nil
       @logger = Logger.instance
       @logger.level = :debug if ENV['PACTO_DEBUG']
+      @callback = Pacto::Hooks::ERBHook.new
     end
 
     def register_contract(contract = nil, *tags)
       Pacto.register_contract(contract, *tags)
     end
+
+    def register_callback(callback = nil, &block)
+      if block_given?
+        @callback = Pacto::Callback.new(&block)
+      else
+        raise 'Expected a Pacto::Callback' unless callback.is_a? Pacto::Callback
+        @callback = callback
+      end
+    end
   end
 end
diff --git a/lib/pacto/core/contract_repository.rb b/lib/pacto/core/contract_repository.rb
index c5a843e..65d08f7 100644
--- a/lib/pacto/core/contract_repository.rb
+++ b/lib/pacto/core/contract_repository.rb
@@ -10,15 +10,13 @@ def register_contract(contract = nil, *tags)
       registered.count - start_count
     end
 
-    def use(tag, values = nil)
-      merged_contracts = registered[:default].merge registered[tag]
+    def use(tag, values = {})
+      merged_contracts = registered[:default] + registered[tag]
 
       raise ArgumentError, "contract \"#{tag}\" not found" if merged_contracts.empty?
 
-      configuration.provider.values = values
-
       merged_contracts.each do |contract|
-        contract.stub!
+        contract.stub_contract! values
       end
       merged_contracts.count
     end
@@ -30,5 +28,17 @@ def registered
     def unregister_all!
       registered.clear
     end
+
+    def contract_for(request_signature)
+      matches = Set.new
+      registered.values.each do |contract_set|
+        contract_set.each do |contract|
+          if contract.matches? request_signature
+            matches.add contract
+          end
+        end
+      end
+      matches
+    end
   end
 end
diff --git a/lib/pacto/hooks/erb_hook.rb b/lib/pacto/hooks/erb_hook.rb
new file mode 100644
index 0000000..282dc9c
--- /dev/null
+++ b/lib/pacto/hooks/erb_hook.rb
@@ -0,0 +1,17 @@
+module Pacto
+  module Hooks
+    class ERBHook < Pacto::Callback
+      def initialize
+        @processor = ERBProcessor.new
+      end
+
+      def process(contracts, request_signature, response)
+        bound_values = contracts.empty? ? {} : contracts.first.values
+        bound_values.merge!({:req => { 'HEADERS' => request_signature.headers}})
+        response.body = @processor.process response.body, bound_values
+        response.body
+      end
+
+    end
+  end
+end
diff --git a/lib/pacto/stubs/built_in.rb b/lib/pacto/stubs/built_in.rb
index 54272f6..ecc18af 100644
--- a/lib/pacto/stubs/built_in.rb
+++ b/lib/pacto/stubs/built_in.rb
@@ -1,13 +1,12 @@
 module Pacto
   module Stubs
     class BuiltIn
-      attr_accessor :values
 
       def initialize
         register_callbacks
       end
 
-      def stub! request, response
+      def stub_request! request, response
         stub = WebMock.stub_request(request.method, "#{request.host}#{request.path}")
         stub = stub.with(request_details(request)) if Pacto.configuration.strict_matchers
         stub.to_return({
@@ -17,28 +16,20 @@ def stub! request, response
           })
       end
 
-      def process(request_signature, response)
-        unless processor.nil?
-          bound_values = {}
-          bound_values.merge!({:req => {'HEADERS' => request_signature.headers}}) if processor.class == ERBProcessor
-          bound_values.merge! @values unless @values.nil?
-          response.body = processor.process response.body, bound_values
-        end
-        response.body
+      def reset!
+        WebMock.reset!
+        WebMock.reset_callbacks
       end
 
       private
 
       def register_callbacks
         WebMock.after_request do |request_signature, response|
-          process request_signature, response
+          contracts = Pacto.contract_for request_signature
+          Pacto.configuration.callback.process contracts, request_signature, response
         end
       end
 
-      def processor
-        Pacto.configuration.postprocessor
-      end
-
       def format_body(body)
         if body.is_a?(Hash) || body.is_a?(Array)
           body.to_json
diff --git a/spec/integration/e2e_spec.rb b/spec/integration/e2e_spec.rb
index 2d591e3..27cff10 100644
--- a/spec/integration/e2e_spec.rb
+++ b/spec/integration/e2e_spec.rb
@@ -39,19 +39,21 @@
 
   context 'Journey' do
     it 'stubs multiple services with a single use' do
-
       Pacto.configure do |c|
+        c.strict_matchers = false
         c.postprocessor = Pacto::ERBProcessor.new
         c.preprocessor = nil
+        c.register_callback Pacto::Hooks::ERBHook.new
       end
 
+      # Preprocessor must be off before building!
       login_contract = Pacto.build_from_file(contract_path, 'http://dummyprovider.com')
       contract = Pacto.build_from_file(strict_contract_path, 'http://dummyprovider.com')
-
       Pacto.configure do |c|
         c.register_contract login_contract, :default
         c.register_contract contract, :devices
       end
+
       Pacto.use(:devices, {:device_id => 42})
 
       raw_response = HTTParty.get('http://dummyprovider.com/hello', headers: {'Accept' => 'application/json' })
diff --git a/spec/integration/spec_helper.rb b/spec/integration/spec_helper.rb
deleted file mode 100644
index e69de29..0000000
diff --git a/spec/integration/templating_spec.rb b/spec/integration/templating_spec.rb
index fd5afa7..5e0cf70 100644
--- a/spec/integration/templating_spec.rb
+++ b/spec/integration/templating_spec.rb
@@ -30,6 +30,9 @@
         c.preprocessor = nil
         c.postprocessor = nil
         c.strict_matchers = false
+        c.register_callback do |contracts, req, res|
+          res
+        end
       end
 
       expect(response.keys).to eq ['message']
@@ -41,6 +44,7 @@
     it 'processes erb on each request' do
       Pacto.configure do |c|
         c.preprocessor = nil
+        c.strict_matchers = false
         c.postprocessor = Pacto::ERBProcessor.new
       end
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 12c0a35..fe58891 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -8,4 +8,11 @@
   config.expect_with :rspec do |c|
     c.syntax = :expect
   end
+  config.before(:each) do
+    provider = Pacto.configuration.provider
+    unless provider.respond_to? :reset!
+      provider.stub(:reset!)
+    end
+    Pacto.clear!
+  end
 end
diff --git a/spec/unit/hooks/erb_hook_spec.rb b/spec/unit/hooks/erb_hook_spec.rb
new file mode 100644
index 0000000..d23cc6d
--- /dev/null
+++ b/spec/unit/hooks/erb_hook_spec.rb
@@ -0,0 +1,51 @@
+describe Pacto::Hooks::ERBHook do
+  describe '.process' do
+    let(:req) {
+      OpenStruct.new({:headers => {'User-Agent' => 'abcd'}})
+    }
+    let(:converted_req) {
+      {'HEADERS' => {'User-Agent' => 'abcd'}}
+    }
+    let(:res) {
+      OpenStruct.new({:body => 'before'})
+    }
+
+    before do
+    end
+
+    context 'no matching contracts' do
+      it 'binds the request' do
+        contracts = Set.new
+        mock_erb({ :req => converted_req })
+        described_class.new.process contracts, req, res
+        expect(res.body).to eq('after')
+      end
+    end
+
+    context 'one matching contract' do
+      it 'binds the request and the contract\'s values' do
+        contract = OpenStruct.new({:values => {:max => 'test'}})
+        contracts = Set.new([contract])
+        mock_erb({ :req => converted_req, :max => 'test'})
+        described_class.new.process contracts, req, res
+        expect(res.body).to eq('after')
+      end
+    end
+
+    context 'multiple matching contracts' do
+      it 'binds the request and the first contract\'s values' do
+        contract1 = OpenStruct.new({:values => {:max => 'test'}})
+        contract2 = OpenStruct.new({:values => {:mob => 'team'}})
+        res = OpenStruct.new({:body => 'before'})
+        mock_erb({ :req => converted_req, :max => 'test'})
+        contracts = Set.new([contract1, contract2])
+        described_class.new.process contracts, req, res
+        expect(res.body).to eq('after')
+      end
+    end
+  end
+
+  def mock_erb(hash)
+    Pacto::ERBProcessor.any_instance.should_receive(:process).with('before', hash).and_return('after')
+  end
+end
diff --git a/spec/unit/pacto/contract_spec.rb b/spec/unit/pacto/contract_spec.rb
index 8c23921..0a2c0ab 100644
--- a/spec/unit/pacto/contract_spec.rb
+++ b/spec/unit/pacto/contract_spec.rb
@@ -1,23 +1,23 @@
 module Pacto
   describe Contract do
     let(:request)  { double 'request' }
+    let(:request_signature)  { double 'request_signature' }
     let(:response) { double 'response' }
-
-    let(:contract) { described_class.new request, response }
     let(:provider) { double 'provider' }
+    let(:instantiated_response) { double 'instantiated response' }
 
-    describe '#stub!' do
-      before do
-        response.stub(:instantiate => instantiated_response)
-        Pacto.configuration.provider = provider
-      end
+    subject(:contract) { described_class.new request, response }
 
-      let(:instantiated_response) { double 'instantiated response' }
+    before do
+      response.stub(:instantiate => instantiated_response)
+      Pacto.configuration.provider = provider
+    end
 
+    describe '#stub_contract!' do
       it 'instantiates the response and registers a stub' do
         response.should_receive :instantiate
-        provider.should_receive(:stub!).with request, instantiated_response
-        contract.stub!
+        provider.should_receive(:stub_request!).with request, instantiated_response
+        contract.stub_contract!
       end
     end
 
@@ -51,5 +51,28 @@ module Pacto
         end
       end
     end
+
+    describe '#matches?' do
+      let(:request_matcher) do
+        double('fake request matcher').tap do |matcher|
+          matcher.stub(:matches?) { |r| r == request_signature }
+        end
+      end
+
+      context 'when the contract is not stubbed' do
+        it 'returns false' do
+          expect(contract.matches? request_signature).to be_false
+        end
+      end
+
+      context 'when the contract is stubbed' do
+        it 'returns true if it matches the request' do
+          provider.should_receive(:stub_request!).with(request, instantiated_response).and_return(request_matcher)
+          contract.stub_contract!
+          expect(contract.matches? request_signature).to be_true
+          expect(contract.matches? :anything).to be_false
+        end
+      end
+    end
   end
 end
diff --git a/spec/unit/pacto/core/configuration_spec.rb b/spec/unit/pacto/core/configuration_spec.rb
index 79d4faa..6860597 100644
--- a/spec/unit/pacto/core/configuration_spec.rb
+++ b/spec/unit/pacto/core/configuration_spec.rb
@@ -16,5 +16,13 @@
       end
       expect(Pacto.configuration.contracts_path).to eq(contracts_path)
     end
+
+    it 'register a Pacto Callback' do
+      callback_block = Pacto::Callback.new { }
+      Pacto.configure do |c|
+        c.register_callback(callback_block)
+      end
+      expect(Pacto.configuration.callback).to eq(callback_block)
+    end
   end
 end
diff --git a/spec/unit/pacto/core/contract_repository_spec.rb b/spec/unit/pacto/core/contract_repository_spec.rb
index c048679..099069d 100644
--- a/spec/unit/pacto/core/contract_repository_spec.rb
+++ b/spec/unit/pacto/core/contract_repository_spec.rb
@@ -70,13 +70,13 @@
       let(:response_body) { double('response_body') }
 
       it 'stubs a contract with default values' do
-        contract.should_receive(:stub!)
-        another_contract.should_receive(:stub!)
+        contract.should_receive(:stub_contract!)
+        another_contract.should_receive(:stub_contract!)
         expect(described_class.use(tag)).to eq 2
       end
 
       it 'stubs default contract if unused tag' do
-        another_contract.should_receive(:stub!)
+        another_contract.should_receive(:stub_contract!)
         expect(described_class.use(another_tag)).to eq 1
       end
     end
@@ -96,4 +96,38 @@
       expect(described_class.registered).to be_empty
     end
   end
+
+  describe '.contract_for' do
+    let(:request_signature) { double('request signature') }
+
+    context 'when no contracts are found for a request' do
+      it 'returns an empty list' do
+        expect(described_class.contract_for request_signature).to be_empty
+      end
+    end
+
+    context 'when contracts are found for a request' do
+      let(:contracts_that_match)      { create_contracts 2, true }
+      let(:contracts_that_dont_match) { create_contracts 3, false }
+      let(:all_contracts)             { contracts_that_match + contracts_that_dont_match }
+
+      it 'returns the matching contracts' do
+        register_and_use all_contracts
+        expect(described_class.contract_for request_signature).to eq(contracts_that_match)
+      end
+    end
+  end
+
+  def create_contracts(total, matches)
+    total.times.map do
+      double('contract',
+             :stub_contract! => double('request matcher'),
+             :matches? => matches)
+    end.to_set
+  end
+
+  def register_and_use contracts
+    contracts.each { |contract| described_class.register_contract contract }
+    Pacto.use :default
+  end
 end
diff --git a/spec/unit/pacto/stubs/built_in_spec.rb b/spec/unit/pacto/stubs/built_in_spec.rb
index 34e239a..eb4994f 100644
--- a/spec/unit/pacto/stubs/built_in_spec.rb
+++ b/spec/unit/pacto/stubs/built_in_spec.rb
@@ -38,7 +38,7 @@ module Stubs
         end
       end
 
-      describe '#stub!' do
+      describe '#stub_request!' do
         before do
           WebMock.should_receive(:stub_request).
             with(request.method, "#{request.host}#{request.path}").
@@ -65,7 +65,7 @@ module Stubs
 
             stubbed_request.stub(:with).and_return(stubbed_request)
 
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
 
@@ -83,7 +83,7 @@ module Stubs
 
             stubbed_request.stub(:with).and_return(stubbed_request)
 
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
 
@@ -99,7 +99,7 @@ module Stubs
 
             stubbed_request.stub(:with).and_return(stubbed_request)
 
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
 
@@ -110,7 +110,7 @@ module Stubs
             stubbed_request.should_receive(:with).
               with({:headers => request.headers, :query => request.params}).
               and_return(stubbed_request)
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
 
@@ -121,7 +121,7 @@ module Stubs
             stubbed_request.should_receive(:with).
               with({:headers => request.headers, :body => request.params}).
               and_return(stubbed_request)
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
 
@@ -140,7 +140,7 @@ module Stubs
             stubbed_request.should_receive(:with).
               with({:query => request.params}).
               and_return(stubbed_request)
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
 
@@ -159,7 +159,7 @@ module Stubs
             stubbed_request.should_receive(:with).
               with({}).
               and_return(stubbed_request)
-            described_class.new.stub! request, response
+            described_class.new.stub_request! request, response
           end
         end
       end
diff --git a/spec/unit/spec_helper.rb b/spec/unit/spec_helper.rb
deleted file mode 100644
index 12e752a..0000000
--- a/spec/unit/spec_helper.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-require 'coveralls_helper'
-
-RSpec.configure do |config|
-  config.before(:each) do
-    Pacto.clear!
-  end
-end