MitoCheck is an Integrated Project (IP) funded by the European Union under its Sixth Framework Program (FP6). The project started in 2004 and ended successfully in 2009. MitoCheck was coordinated by the Research Institute of Molecular Pathology (IMP) in Vienna. During the five-year period, the MitoCheck consortium has developed and applied technologies that have enabled a systematic analysis of genes and proteins that are required for chromosome segregation and cell division in human cells. All 22,000 human genes were inactivated one by one in cultured human cells using RNA interference (RNAi). The cellular phenotypes upon the RNAi treatment were recorded by high-throughput live cell imaging. Automated analyses of the resulting images and movies revealed that some 600 out of the 22,000 human genes play a role in mitosis. For many of these mitotic proteins, their sub-cellular localization at different stages of the cell cycle and their interaction partners have also been identified by MitoCheck.