diff --git a/app/models/contract.rb b/app/models/contract.rb
index 87e5de6..e734b7a 100644
--- a/app/models/contract.rb
+++ b/app/models/contract.rb
@@ -48,6 +48,22 @@ class Contract < ActiveRecord::Base
     read_attribute(:status) || "open"
   end
 
+  def lock!
+    update_attribute(:status, "locked")
+  end
+
+  def close!
+    update_attribute(:status, "closed")
+  end
+
+  def locked?
+    self.status == "locked"
+  end
+
+  def closed?
+    self.status == "closed"
+  end
+
   # ------------------------------------------------------------
   # Labor Methods
   # ------------------------------------------------------------
diff --git a/app/models/deliverable.rb b/app/models/deliverable.rb
index fa93bf9..e52aeb6 100644
--- a/app/models/deliverable.rb
+++ b/app/models/deliverable.rb
@@ -55,6 +55,22 @@ class Deliverable < ActiveRecord::Base
     nil
   end
 
+  def lock!
+    update_attribute(:status, "locked")
+  end
+
+  def close!
+    update_attribute(:status, "closed")
+  end
+
+  def locked?
+    self.status == "locked"
+  end
+
+  def closed?
+    self.status == "closed"
+  end
+
   def to_s
     title
   end
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 661837d..0001f08 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -1,4 +1,10 @@
 en:
+  activerecord:
+    errors:
+      messages:
+        cant_to_closed_deliverable: "Can't create a time entry on a closed deliverable"
+        cant_to_closed_contract: "Can't create a time entry on a closed contract"
+
   field_end_date: End Date
   field_executed: Executed
   text_contracts: Contracts
diff --git a/init.rb b/init.rb
index 19e673c..eb3c616 100644
--- a/init.rb
+++ b/init.rb
@@ -62,6 +62,9 @@ end
 
 require 'dispatcher'
 Dispatcher.to_prepare :redmine_contracts do
+
+  require_dependency 'time_entry'
+  TimeEntry.send(:include, RedmineContracts::Patches::TimeEntryPatch)
   gem 'inherited_resources', :version => '1.0.6'
   require_dependency 'inherited_resources'
   require_dependency 'inherited_resources/base'
diff --git a/lib/redmine_contracts/patches/time_entry_patch.rb b/lib/redmine_contracts/patches/time_entry_patch.rb
new file mode 100644
index 0000000..58f9d69
--- /dev/null
+++ b/lib/redmine_contracts/patches/time_entry_patch.rb
@@ -0,0 +1,36 @@
+module RedmineContracts
+  module Patches
+    module TimeEntryPatch
+      def self.included(base)
+        base.extend(ClassMethods)
+
+        base.send(:include, InstanceMethods)
+        base.class_eval do
+          unloadable
+
+          validate :validate_deliverable_status
+          validate :validate_contract_status
+
+          def validate_deliverable_status
+            if issue.present? && issue.deliverable.present?
+              errors.add_to_base(:cant_to_closed_deliverable) if issue.deliverable.closed?
+            end
+          end
+
+          def validate_contract_status
+            if issue.present? && issue.deliverable.present? && issue.deliverable.contract.present?
+              errors.add_to_base(:cant_to_closed_contract) if issue.deliverable.contract.closed?
+            end
+          end
+          
+        end
+      end
+
+      module ClassMethods
+      end
+
+      module InstanceMethods
+      end
+    end
+  end
+end
diff --git a/test/unit/lib/redmine_contracts/patches/time_entry_patch_test.rb b/test/unit/lib/redmine_contracts/patches/time_entry_patch_test.rb
new file mode 100644
index 0000000..d844c15
--- /dev/null
+++ b/test/unit/lib/redmine_contracts/patches/time_entry_patch_test.rb
@@ -0,0 +1,109 @@
+require File.dirname(__FILE__) + '/../../../../test_helper'
+
+class RedmineContracts::Patches::TimeEntryTest < ActionController::TestCase
+
+  def setup
+    @project = Project.generate!
+    @contract = Contract.generate!(:project => @project, :status => 'open')
+    @deliverable = FixedDeliverable.generate!(:contract => @contract, :status => 'open').reload
+    @issue = Issue.generate_for_project!(@project, :deliverable => @deliverable).reload
+    assert_equal @deliverable, @issue.deliverable
+    @user = User.generate!
+    @role = Role.generate!
+    User.add_to_project(@user, @project, @role)
+    @activity = TimeEntryActivity.generate!
+  end
+
+  def create_time_entry
+    @issue.reload
+    @time_entry = TimeEntry.create(:issue => @issue,
+                                   :project => @project,
+                                   :spent_on => Date.today,
+                                   :activity => @activity,
+                                   :hours => 10,
+                                   :user => @user)
+  end
+
+  def assert_error_about_closed_deliverable(time_entry)
+    assert_equal "Can't create a time entry on a closed deliverable", time_entry.errors.on_base
+  end
+
+  def assert_error_about_closed_contract(time_entry)
+    assert_equal "Can't create a time entry on a closed contract", time_entry.errors.on_base
+  end
+
+  should "allow logging time to an issue on an open deliverable, open contract" do
+    assert_difference("TimeEntry.count") { create_time_entry }
+  end
+
+  should "allow logging time to an issue on a locked deliverable, open contract" do
+    assert @deliverable.lock!
+    assert @deliverable.locked?
+    
+    assert_difference("TimeEntry.count") { create_time_entry }
+  end
+
+  should "allow logging time to an issue on an open deliverable, locked contract" do
+    assert @contract.lock!
+    assert @contract.locked?
+
+    assert_difference("TimeEntry.count") { create_time_entry }
+  end
+  
+  should "allow logging time to an issue on a locked deliverable, locked contract" do
+    assert @deliverable.lock!
+    assert @deliverable.locked?
+    assert @contract.lock!
+    assert @contract.locked?
+
+    assert_difference("TimeEntry.count") { create_time_entry }
+  end
+
+  should "block logging time to an issue on a closed deliverable, open contract" do
+    assert @deliverable.close!
+    assert @deliverable.closed?
+    
+    assert_no_difference("TimeEntry.count") { create_time_entry }
+    assert_error_about_closed_deliverable(@time_entry)
+  end
+
+  should "block logging time to an issue on a closed deliverable, locked contract" do
+    assert @deliverable.close!
+    assert @deliverable.closed?
+    assert @contract.lock!
+    assert @contract.locked?
+    
+    assert_no_difference("TimeEntry.count") { create_time_entry }
+    assert_error_about_closed_deliverable(@time_entry)
+  end
+
+  should "block logging time to an issue on an open deliverable, closed contract" do
+    assert @contract.close!
+    assert @contract.closed?
+    
+    assert_no_difference("TimeEntry.count") { create_time_entry }
+    assert_error_about_closed_contract(@time_entry)
+  end
+
+  should "block logging time to an issue on a locked deliverable, closed contract" do
+    assert @deliverable.lock!
+    assert @deliverable.locked?
+    assert @contract.close!
+    assert @contract.closed?
+    
+    assert_no_difference("TimeEntry.count") { create_time_entry }
+    assert_error_about_closed_contract(@time_entry)
+  end
+  
+  should "block logging time to an issue on a closed deliverable, closed contract" do
+    assert @deliverable.close!
+    assert @deliverable.closed?
+    assert @contract.close!
+    assert @contract.closed?
+    
+    assert_no_difference("TimeEntry.count") { create_time_entry }
+    assert @time_entry.errors.on_base.include?("Can't create a time entry on a closed deliverable")
+    assert @time_entry.errors.on_base.include?("Can't create a time entry on a closed contract")
+  end
+  
+end