diff --git a/app/models/deliverable.rb b/app/models/deliverable.rb
index 1a7ddef..78a395d 100644
--- a/app/models/deliverable.rb
+++ b/app/models/deliverable.rb
@@ -33,6 +33,9 @@ class Deliverable < ActiveRecord::Base
   delegate "locked?", :to => :contract, :prefix => true, :allow_nil => true
 
   # Callbacks
+  before_destroy :block_on_locked_contracts
+  before_destroy :block_on_closed_contracts
+  
   def after_initialize
     self.status = "open" unless self.status.present?
   end
@@ -139,6 +142,14 @@ class Deliverable < ActiveRecord::Base
   def noop(message="")
   end
 
+  def block_on_locked_contracts
+    !contract_locked?
+  end
+
+  def block_on_closed_contracts
+    !contract_closed?
+  end
+
   def to_s
     title
   end
diff --git a/app/views/deliverables/_details_row.html.erb b/app/views/deliverables/_details_row.html.erb
index 10bcc4c..c301f60 100644
--- a/app/views/deliverables/_details_row.html.erb
+++ b/app/views/deliverables/_details_row.html.erb
@@ -7,7 +7,7 @@
                   <div class="info">
                     <div class="title">
                       <%= link_to(l(:button_edit), edit_contract_deliverable_path(@project, contract, deliverable), :class => 'icon icon-edit') %>
-                      <%= link_to(l(:button_delete), contract_deliverable_path(@project, contract, deliverable), :method => :delete, :confirm => l(:text_are_you_sure), :class => 'icon icon-del') %>
+                      <%= link_to(l(:button_delete), contract_deliverable_path(@project, contract, deliverable), :method => :delete, :confirm => l(:text_are_you_sure), :class => 'icon icon-del') if contract.open? %>
                     </div>
                     
                     <%= textilizable(deliverable, :notes) %>
diff --git a/test/unit/deliverable_test.rb b/test/unit/deliverable_test.rb
index 08b2d75..fa32573 100644
--- a/test/unit/deliverable_test.rb
+++ b/test/unit/deliverable_test.rb
@@ -50,6 +50,17 @@ class DeliverableTest < ActiveSupport::TestCase
       assert !deliverable.valid?
       assert deliverable.errors.on_base.include?("Can't create a deliverable on a locked contract")
     end
+
+    should "block deleting a deliverable" do
+      contract = Contract.generate!
+      deliverable = FixedDeliverable.generate!(:contract => contract).reload
+      assert contract.lock!
+
+      assert_no_difference("Deliverable.count") do
+        deliverable.destroy
+      end
+      
+    end
   end
 
   context "with a closed contract" do
@@ -60,5 +71,16 @@ class DeliverableTest < ActiveSupport::TestCase
       assert !deliverable.valid?
       assert deliverable.errors.on_base.include?("Can't create a deliverable on a closed contract")
     end
+
+    should "block deleting a deliverable" do
+      contract = Contract.generate!
+      deliverable = FixedDeliverable.generate!(:contract => contract).reload
+      assert contract.close!
+
+      assert_no_difference("Deliverable.count") do
+        deliverable.destroy
+      end
+      
+    end
   end
 end