Given the ubiquity of electrical devices in the modern day, energy production is of paramount concern. Smartphones, the internet, and climate control systems are almost required for modern living, and all require energy to operate. Subsequently, efficient energy generation is needed as the global population increases. While many renewable energy options are available, hydrogen fuel cells demonstrate the most efficiency. The use of these fuel cells begets the need for clean hydrogen. Methane reforming exists as the most widely used method for hydrogen generation. However, this process also produces greenhouse gas emissions. As such, water electrolysis stands as an attractive option for hydrogen synthesis. In order to split hydrogen and oxygen from water, good electrocatalysts are needed. While there are many options available, transition metal phosphides have demonstrated excellent properties for this application. Low cost, wide availability, and excellent tunability are all hallmarks of transition metal phosphide applications for water electrocatalysis. As such, the synthesis, structures, and electrocatalytic activity of different metal phosphides must be explored if a clean energy future is desired.