Abstract
The current ITK release 2.6 does not contain a way to combine transforms in a structural way. This document describes a contribution to the Insight Toolkit ITK \url{www.itk.org}, which implements what we call an \doxygen{CombinationTransform}. Two ways to combine transforms are implemented, by addition and by composition. Depending on this selection, different implementations of the \code{TransformPoint()} are provided. Also the expressions for the Jacobian and the inverse transform depend on the way transforms are combined. By using function pointers expensive \code{if}-statements are avoided. This paper is accompanied with the source code.