>>I tried using:
>>

>>  public class BaseObject
>>    {
>>        private BaseObject() { }
>>    }
>>

>>to prevent other developers directly creating an instance of the class. I was hoping to sub-class from this and have the behaviour inherited by these classes. Seems that's not possible - in fact I can't sub-class from BaseObject at all because 'BaseObject is inaccessible due to it's protection level'. Any other way to achieve what I need (I don't like the idea of having to put private constructors in all the leaf classes)
>>

>Wouldn't 'protected' in base do what you want?

Do you mean 'protected BaseObject(){}'?
That doesn't prevent creation of the object.... :-{
Thx,
Viv