diff --git a/lib/lograge.rb b/lib/lograge.rb
index b4ca5da6..dfd70cc0 100644
--- a/lib/lograge.rb
+++ b/lib/lograge.rb
@@ -32,6 +32,18 @@ def self.custom_options(event)
     end
   end
 
+  # Before format allows you to change the structure of the output.
+  # You've to pass in something callable
+  #
+  mattr_writer :before_format
+  self.before_format = nil
+
+  def self.before_format(data, payload)
+    result = nil
+    result = @@before_format.call(data, payload) if @@before_format
+    result || data
+  end
+
   # Set conditions for events that should be ignored
   #
   # Currently supported formats are:
@@ -106,6 +118,7 @@ def self.setup(app)
     Lograge.remove_existing_log_subscriptions
     Lograge::RequestLogSubscriber.attach_to :action_controller
     Lograge.custom_options = app.config.lograge.custom_options
+    Lograge.before_format = app.config.lograge.before_format
     Lograge.log_level = app.config.lograge.log_level || :info
     self.support_deprecated_config(app) # TODO: Remove with version 1.0
     Lograge.formatter = app.config.lograge.formatter || Lograge::Formatters::KeyValue.new
diff --git a/lib/lograge/log_subscriber.rb b/lib/lograge/log_subscriber.rb
index a3558ce9..ea9655b6 100644
--- a/lib/lograge/log_subscriber.rb
+++ b/lib/lograge/log_subscriber.rb
@@ -7,7 +7,7 @@ module Lograge
   class RequestLogSubscriber < ActiveSupport::LogSubscriber
     def process_action(event)
       return if Lograge.ignore?(event)
-      
+
       payload = event.payload
 
       data      = extract_request(payload)
@@ -16,6 +16,7 @@ def process_action(event)
       data.merge! location(event)
       data.merge! custom_options(event)
 
+      data = before_format(data, payload)
       formatted_message = Lograge.formatter.call(data)
       logger.send(Lograge.log_level, formatted_message)
     end
@@ -67,6 +68,10 @@ def custom_options(event)
       Lograge.custom_options(event) || {}
     end
 
+    def before_format(data, payload)
+      Lograge.before_format(data, payload)
+    end
+
     def runtimes(event)
       {
         :duration => event.duration,
diff --git a/spec/lograge_logsubscriber_spec.rb b/spec/lograge_logsubscriber_spec.rb
index 5582f564..cbd2d0fd 100644
--- a/spec/lograge_logsubscriber_spec.rb
+++ b/spec/lograge_logsubscriber_spec.rb
@@ -162,6 +162,27 @@
     end
   end
 
+  describe "with before_format configured for lograge output" do
+    before do
+      Lograge.formatter = Lograge::Formatters::KeyValue.new
+      Lograge.before_format = nil
+    end
+
+    it "should output correctly" do
+      Lograge.before_format = lambda { |data, payload|
+        Hash[*data.first].merge(Hash[*payload.first])
+      }
+      subscriber.process_action(event)
+      log_output.string.should include("method=GET")
+      log_output.string.should include("status=200")
+    end
+    it "should work if the method returns nil" do
+      Lograge.before_format = lambda {|data, payload| nil}
+      subscriber.process_action(event)
+      log_output.string.should be_present
+    end
+  end
+
   describe "with ignore configured" do
     before do
       # Lograge::log_format = :lograge