 Microbial fuel cells, MFCs, are devices that convert biological activity into electricity by using bacteria to break down organic compounds. Although they hold great potential for sustainable energy production, their practical application has been limited due to the lack of understanding of the underlying mechanisms involved. Recent studies suggest that the greatest benefit of MFC technology may not be the generation of electricity, but rather the degradation of waste and toxins. This suggests that further research should focus on understanding the microbial processes involved in order to maximize the potential of MFCs. This article was authored by Kelly P. Nevin and Ashley E. Franks.