Is there a way to extended the Hierarchy?

Is there a way do it? I want to create some buttons at the bottom of the window.

Thanks.

I can’t think of any reason why buttons should be inside the hierachy window. Each window has it’s place and provides only those functions that are relevant in it’s context.

The best you can do is create an EditorWindow that contains your buttons and dock it below your hierarchy panel if you want them there.