In my custom control I have overriden CreateChildControls and the first few
lines look like this.

protected override void CreateChildControls()
{
    Debug.WriteLine("CreateChildControls", "FeatureList");
       Controls.Clear();
    ..
}

what I am seeing is that the Controls.Clear line indirectly calls
CreateChildControls (the call is through a Get on the Controls collection
from the stack).

Although the controls end up being right, they are created twice which is
hardly efficient.  What do I need to do to stop this happening?

Iain