Hi there: I have created a product 'X' with a zclass call 'X1'. This X1 zclass in the propertysheet has a Common Instance Property Sheet called 'section' (/Control_Panel/Products/X/X1/propertysheets/common/section), with some properties with default values: ie. one of it's property is call ed 'section1' with the default value 'left side', the type of this property is 'string': section1 'left side' string Then in the views of the zclass I 've added a method "propertysheets/section/manage", so when I create an instance I can enter to this propertysheet. So the problem is here: When I create an instance of this 'X1' zclass an I enter to this propertysheet/section , I can change the default value of 'section1' which was 'left side' to 'center side' for example. But then if i change the original default value of my zclass 'X1' to 'right side' let say. The change will not be reflected in my instance, which is okey because i have change d the value to 'center side' before. Another case is when I create another instance of 'X1' zclass without making any change to the value of 'section1' and click on save changes, then if I change the default value in the zclass, the change will not be reflected in this instance. So the question is: There is a way to recognize when an instance will not take the changes that are make to the default values of a propertysheets (in this case thepropertysheet 'section' ) of a zclass from which they inheritance? I try with this lines in an external method, but nothing: self=self._getOb('instanceTest') # instanceTest is the name of the instance of the 'X1 Zclass' a=getattr(self,'meta_type') b=getattr(self.__class__,'meta_type') # in this example the answer was the same: X1 a=eval('self.__class__.propertysheets.section._propertyMap()') b=eval('self.propertysheets.section._propertyMap()') # the answer was again the same: {'id': 'section1', 'type': 'string','meta': {}, 'mode': 'w'} #I try acceding to the zclass to know if it was different from theinstance... a=eval('self.Control_Panel.Products.X.propertysheets.common.section.property Map()') # the answer not help: {'id': 'section1', 'type': 'string', 'meta': {}}, I cannot found any property or something that help me... I don't know where to look or what to try next....if anybody can help me with this....... Thanks in advance Edgardo