>>>>Sometimes when creating a parent child relationship the child may need to know who it's parent is.
>>>>
>>>>I can do that easy enough by passing the parent reference in the constructor for the child.
>>>>
>>>>In C# do I need to worry about the circular reference I've just created?
>>>
>>>Not 100% sure of your context. Bonnie mentioned the problem with assemblies but I think you're asking about simple objects like:

public class ClassA
>>>    {
>>>        ClassB B;
>>>        public ClassA(ClassB b)
>>>        { B = b; }
>>>    }
>>>
>>>    public class ClassB
>>>    {
>>>        ClassA A;
>>>        public ClassB()
>>>        {A = new ClassA(this);}
>>>    }

If so then there's not a problem. See:http://msdn.microsoft.com/en-us/library/0t81zye4(VS.71).aspx
>>>
>>>Best,
>>>Viv
>>
>>Yep simple objects, all within the same assembly. Parent has a lot of properties/resources that it's children need to be able to work with. Parent won't change once created so no need for events.
>>
>>Somewhere early on I got the idea this was not a desirable pattern and the circular reference between assemblies answers were plugging up my google results. It looked like I was OK, but I wanted to be sure. These are rather major classes.
>>
>>Thanks for the answers everyone.
>
>Whilst the 'circular reference' is not able to cause a real problem it might be worth implementing IDisposable on those classes ?

I was curious about that. Not sure if it would speed up the GC up a bunch or not. The classes I'm doing this on won't change that frequently so I'm not sure it's needed even if it would.