The Component Template Library (CTL) is a C++ Template Library to realise distributed component-based software systems. This middleware was developed at the Institute of Scientific Computing of the University of Braunschweig by Dr. Rainer Niekamp. It is implemented with respect to best performance and also comfortable usage. Comparable Software Technologies are CORBA or CCA (Common Component Architecture). Till to now several programming languages can be coupled easily while using the CTL: C/C++, Fortran, Java and Python.