diff --git a/app/models/deliverable.rb b/app/models/deliverable.rb
index e52aeb6..079bbc6 100644
--- a/app/models/deliverable.rb
+++ b/app/models/deliverable.rb
@@ -20,6 +20,7 @@ class Deliverable < ActiveRecord::Base
   validates_presence_of :type
   validates_presence_of :manager
   validates_inclusion_of :status, :in => ["open","locked","closed"], :allow_blank => true, :allow_nil => true
+  validate :validate_update_allowed
   
   # Accessors
   include DollarizedAttribute
@@ -63,6 +64,10 @@ class Deliverable < ActiveRecord::Base
     update_attribute(:status, "closed")
   end
 
+  def open?
+    self.status == "open"
+  end
+
   def locked?
     self.status == "locked"
   end
@@ -71,6 +76,28 @@ class Deliverable < ActiveRecord::Base
     self.status == "closed"
   end
 
+  def editable?
+    (new_record? || open?)
+  end
+
+  def validate_update_allowed
+    unless new_record?
+      if changes.keys == ["status"]
+        noop("Allow changes to the status only")
+      elsif changes["status"].present? && changes["status"].second == "open"
+        noop("Allow any changes when going to 'open'")
+      elsif changes["status"].present?
+        errors.add_to_base(:cant_update_locked_deliverable) if locked?
+        errors.add_to_base(:cant_update_closed_deliverable) if closed?
+      end
+    end
+  end
+
+  # No operation method, useful to clean up logic with an optional message
+  # for documentation
+  def noop(message="")
+  end
+
   def to_s
     title
   end
diff --git a/app/views/deliverables/_form.html.erb b/app/views/deliverables/_form.html.erb
index b824160..54ddded 100644
--- a/app/views/deliverables/_form.html.erb
+++ b/app/views/deliverables/_form.html.erb
@@ -2,6 +2,12 @@
 <%= javascript_tag("var i18nEndDateEmpty = '#{l(:text_end_date_empty)}'") %>
 <%= javascript_tag("var i18nChangedPeriodMessage = '#{l(:text_changed_period_message)}'") %>
 
+<% if resource.locked? || resource.closed? %>
+  <div class="error_msg">
+    <p><%= resource.locked? ? l(:text_deliverable_locked_warning) : l(:text_deliverable_closed_warning) %></p>
+  </div>
+<% end %>
+
 <div class="box tabular">
 <% form.inputs :name => l(:text_deliverable_details_legend), :id => 'deliverable-details' do %>
   <%# Used by jquery to check if this is a new or existing record %>
diff --git a/config/locales/en.yml b/config/locales/en.yml
index dec6e89..5c260b7 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -6,6 +6,8 @@ en:
         cant_create_time_on_closed_contract: "Can't create a time entry on a closed contract"
         cant_assign_to_closed_deliverable: "Can't assign issue to a closed deliverable"
         cant_assign_to_locked_deliverable: "Can't assign issue to a locked deliverable"
+        cant_update_locked_deliverable: "Can't update a locked deliverable"
+        cant_update_closed_deliverable: "Can't update a closed deliverable"
 
   field_end_date: End Date
   field_executed: Executed
@@ -89,4 +91,5 @@ en:
   text_error_message_orphaned_time: "There is {{amount}} worth of time clocked to issues that are not assigned to any deliverables."
   text_error_message_update_orphaned_time: "Please update the orphaned issues."
   field_estimated: Estimated
-  
+  text_deliverable_locked_warning: "This deliverable is locked and cannot be saved without changing it's status to Open."
+  text_deliverable_closed_warning: "This deliverable is closed and cannot be saved without changing it's status to Open."
diff --git a/test/integration/deliverables_edit_test.rb b/test/integration/deliverables_edit_test.rb
index cde9edc..55a5c98 100644
--- a/test/integration/deliverables_edit_test.rb
+++ b/test/integration/deliverables_edit_test.rb
@@ -9,7 +9,7 @@ class DeliverablesEditTest < ActionController::IntegrationTest
     @manager = User.generate!
     @role = Role.generate!
     User.add_to_project(@manager, @project, @role)
-    @fixed_deliverable = FixedDeliverable.generate!(:contract => @contract, :manager => @manager, :title => 'The Title')
+    @fixed_deliverable = FixedDeliverable.generate!(:contract => @contract, :manager => @manager, :title => 'The Title', :notes => "", :feature_sign_off => false, :warranty_sign_off => false)
     @hourly_deliverable = HourlyDeliverable.generate!(:contract => @contract, :manager => @manager, :title => 'An Hourly')
     
     @user = User.generate_user_with_permission_to_manage_budget(:project => @project)
@@ -475,4 +475,168 @@ class DeliverablesEditTest < ActionController::IntegrationTest
     assert_equal 3, @retainer_deliverable.fixed_budgets.count
     assert_equal [600, nil, nil], @retainer_deliverable.fixed_budgets.collect(&:budget)
   end
+
+  context "locked deliverable" do
+    setup do
+      assert @fixed_deliverable.lock!
+    end
+    
+    should "block edits to locked deliverables" do
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        fill_in "Title", :with => 'An updated title'
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'deliverables/edit'
+
+      assert_not_equal "An updated title", @fixed_deliverable.reload.title
+    end
+
+    should "block edits to locked deliverables even when status changes to closed" do
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        fill_in "Title", :with => 'An updated title'
+        select "Closed", :from => "Status"
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'deliverables/edit'
+
+      assert_not_equal "An updated title", @fixed_deliverable.reload.title
+      assert @fixed_deliverable.reload.locked?
+    end
+    
+    should "be allowed to change the status on a locked deliverables to open" do
+      assert @fixed_deliverable.lock!
+      
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        select "Open", :from => "Status"
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'contracts/show'
+
+      assert @fixed_deliverable.reload.open?
+    end
+
+    should "be allowed to change the status on a locked deliverables to closed" do
+      assert @fixed_deliverable.lock!
+      
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        select "Closed", :from => "Status"
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'contracts/show'
+
+      assert @fixed_deliverable.reload.closed?
+    end
+    
+  end
+
+  context "closed deliverable" do
+    setup do
+      assert @fixed_deliverable.close!
+    end
+    
+    should "block edits to closed deliverables" do
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        fill_in "Title", :with => 'An updated title'
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'deliverables/edit'
+
+      assert_not_equal "An updated title", @fixed_deliverable.reload.title
+    end
+
+    should "block edits to closed deliverables even when the status is changed to locked" do
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        fill_in "Title", :with => 'An updated title'
+        select "Locked", :from => "Status"
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'deliverables/edit'
+
+      assert_not_equal "An updated title", @fixed_deliverable.reload.title
+      assert @fixed_deliverable.reload.closed?
+    end
+
+    should "be allowed to change the status on a closed deliverables to open" do
+      assert @fixed_deliverable.close!
+      
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        select "Open", :from => "Status"
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'contracts/show'
+
+      assert @fixed_deliverable.reload.open?
+    end
+
+    should "be allowed to change the status on a closed deliverables to Locked" do
+      assert @fixed_deliverable.lock!
+      
+      visit_contract_page(@contract)
+      click_link_within "#deliverable_details_#{@fixed_deliverable.id}", 'Edit'
+      assert_response :success
+
+      within("#deliverable-details") do
+        select "Locked", :from => "Status"
+      end
+
+      click_button "Save"
+
+      assert_response :success
+      assert_template 'contracts/show'
+
+      assert @fixed_deliverable.reload.locked?
+    end
+  end
+  
+
+
 end