[[Describe.]] Three senses: * Tk within frame of other application (written in, for example, Visual C++). So far, only works--barely--with IE. * Other application within frame of Tk * Tk application that also invokes, say, MFC widgets. [Jeffrey Hobbs] and [David Gravereaux] know the most about these. None of them really work as of January 2002 without a lot of fiddling ... [Arjen Markus] There may be a connection with [Drawing Into Foreign Windows]. [Frame] and [toplevel] bear on this topic. [[Explain tangential connections of [TclScript] and [GPS] work.]]