Mitochondria have recently emerged as intriguing targets for anticancer drugs. A variety of compounds have been now identified that act via mitochondria. These compounds, termed mitocans (an acronym for mitochondria and cancer), destabilise mitochondria and cause apoptosis, which is, at least in some cases, selective for cancer cells. Mitochondria are the powerhouse of the cell, providing it with energy, as well as the source of important mediators of apoptosis. Recent findings show that individual types of cancers are complex and can differ considerably in their array of DNA mutations, harbouring different sets of genetic causes. This indicates that it will be very unlikely to cure cancer by drugs targeting only a few gene products or single pathways that are essential for tumour survival. What is needed then is an invariant target, common to all cells, but which is predominantly only affected by drugs when delivered inside the cancer cells. Such targets appear to be mitochondria, with very rare mutations, and mitocans can be expected to be very efficient drugs of choice for a number of different types of the neoplastic disease.