Recent studies show that microbial fuel cells are a potential alternative to fossil fuels. Due to the current energy crisis, this technology has drawn increasing attention from the scientific community. Research efforts have been focused on improving the performance of these devices and reducing their cost, in order to make it possible the feasibility of MFC designs. Promising results have been achieved but much improvement is still needed. This work looks into the latest advances in the MFC field, covering materials, types of substrate, configuration and operating conditions, among other issues. Thanks to these new developments, which are key to understand MFC design and optimization, microbial fuel cells have become increasingly efficient systems. Keywords: microbial fuel cells, electrodes, separator, substrate, operation conditions, MFC models, ionic liquids.