Metallic platinum has been and still is the most active electrocatalyst for several reactions, including the oxygen reduction reaction (ORR). This reaction, in which gaseous oxygen is reduced to water, is the cathode process for polymer electrolyte membrane fuel cells (PEMFC) and among them the direct methanol fuel cell. The ORR reaction mechanism and kinetics has been thoroughly studied for different Pt morphologies along the development of the fuel cell. Moreover, PEMFC performance for a Pt catalyst obtained by different synthesis methods and employing different supports or electrode substrates have also been vastly studied. As the noble metal presents some cost issues related to its natural abundance, the most recent research has pointed out to reducing the amount of Pt as an electrocatalyst. Nonetheless, several aspects of Pt catalysts are still being under survey such as different particle morphologies, modification by alloying, and the study of durability issues in a fuel-cell device environment.