The FreeFrame SDK aims at helping developers of FreeFrame plugins by providing a default implementation of most of the functions defined in the FreeFrame specification. Developers can thus concentrate their efforts on the few most important functions determining the external behavior of the plugin, namely processFrame and processFrameCopy (for more information about the FreeFrame functions see the FreeFrame specification at www.freeframe.org). The FreeFrame SDK has been designed and implemented on Windows platforms using Microsoft Visual Studio. It is written in C++ and it is available for both Microsoft Visual Studio 6 and Microsoft Visual Studio .NET. However, it can be easily ported to other development environments and other operating systems (e.g., Linux). The FreeFrame SDK is distributed as a collection of header files to be included by the header files of the FreeFrame plugins using it, and as a library file to be statically linked in the DLLs implementing the FreeFrame plugins.