The present article attempts to summarise the elements of the mechanism of action of the antitumor drug cis¯-Platin presented the last few years. Highlights on the discovery, of the drug and the development of it’s second generation derivatives are presented, as well as the ways that cis¯-DDP reacts with biomolecules as DNA and proteins and their models e.g. nucleosides, nucleotides. Also the hydrolysis data are presented for cis¯-DDP and its’ inactive congener trans¯-DDP, as well as for the second generation drug carboplatin. Finally, usefull conclusions are given from this work, pointing out the unanswered questions about the action of cis¯-DDP as well as its differences in action, in comparison with trans¯-DDP.