diff --git a/lib/cancan/ability.rb b/lib/cancan/ability.rb
index 0d953bc..0730b61 100644
--- a/lib/cancan/ability.rb
+++ b/lib/cancan/ability.rb
@@ -219,6 +219,8 @@ module CanCan
       if cannot?(action, subject, *args)
         message ||= unauthorized_message(action, subject)
         raise AccessDenied.new(message, action, subject)
+      else
+        fully_authorized!(action, subject) unless subject.kind_of?(Symbol) && has_instance_conditions?(action, subject)
       end
     end
 
@@ -246,6 +248,20 @@ module CanCan
       relevant_rules(action, subject).any?(&:only_raw_sql?)
     end
 
+    def has_instance_conditions?(action, subject)
+      relevant_rules(action, subject).any?(&:instance_conditions?)
+    end
+
+    def fully_authorized?(action, subject)
+      @fully_authorized ||= []
+      @fully_authorized.include? [action, subject]
+    end
+
+    def fully_authorized!(action, subject)
+      @fully_authorized ||= []
+      @fully_authorized << [action, subject]
+    end
+
     private
 
     def unauthorized_message_keys(action, subject)
diff --git a/lib/cancan/rule.rb b/lib/cancan/rule.rb
index 9c22b27..8d32bfb 100644
--- a/lib/cancan/rule.rb
+++ b/lib/cancan/rule.rb
@@ -51,6 +51,10 @@ module CanCan
       @block.nil? && !conditions_empty? && !@conditions.kind_of?(Hash)
     end
 
+    def instance_conditions?
+      @block || !conditions_empty?
+    end
+
     def conditions_empty?
       @conditions == {} || @conditions.nil?
     end
diff --git a/spec/cancan/ability_spec.rb b/spec/cancan/ability_spec.rb
index 35a97fd..423fb60 100644
--- a/spec/cancan/ability_spec.rb
+++ b/spec/cancan/ability_spec.rb
@@ -235,6 +235,48 @@ describe CanCan::Ability do
   end
 
 
+  # Sufficient Check
+
+  it "is not fully authorized when no authorize! call is made" do
+    @ability.can :update, :ranges, :begin => 1
+    @ability.can?(:update, :ranges).should be_true
+    @ability.should_not be_fully_authorized(:update, :ranges)
+  end
+
+  it "is fully authorized when calling authorize! with a matching action and subject" do
+    @ability.can :update, :ranges
+    @ability.authorize! :update, :ranges
+    @ability.should be_fully_authorized(:update, :ranges)
+    @ability.should_not be_fully_authorized(:create, :ranges)
+  end
+
+  it "is fully authorized when marking action and subject as such" do
+    @ability.fully_authorized! :update, :ranges
+    @ability.should be_fully_authorized(:update, :ranges)
+  end
+
+  it "is not fully authorized when a conditions hash exists but no instance is used" do
+    @ability.can :update, :ranges, :begin => 1
+    @ability.authorize! :update, :ranges
+    @ability.should_not be_fully_authorized(:update, :ranges)
+  end
+
+  it "is not fully authorized when a block exists but no instance is used" do
+    @ability.can :update, :ranges do |range|
+      range.begin == 1
+    end
+    @ability.authorize! :update, :ranges
+    @ability.should_not be_fully_authorized(:update, :ranges)
+  end
+
+  it "is not fully authorized when attributes are required but not checked on in update/destroy actions" do
+    pending
+    @ability.can :update, :users, :name
+    @ability.authorize! :update, :users
+    @ability.should_not be_fully_authorized(:update, :users)
+  end
+
+
   # Cannot
 
   it "offers cannot? method which inverts can?" do