Most people think of online courses when they talk about e-learning, but aspects of social media can also be considered e-learning. In 2011 the Knowledge for Health Project (K4Health) began work with local partners to implement an e-learning and professional development policy for Medical Laboratory Scientists based on the needs identified by United States Agency for International Development (USAID)/Nigeria. Six e-learning courses were developed and promoted through several channels including social media. A Facebook Group was created to share information about accessing and navigating the courses and attracted 8,500 members in 18 months. As the Group grew, the topics discussed evolved to include trade union news, employment opportunities and technical resources. Another Facebook Group provided insights that Facebook Groups could be used to facilitate interactions focused on continuing professional development. The findings show that Facebook Groups accommodate an informal learning style, allowing individuals to learn through peer support in flexible ways. It has also shown that the use of Facebook Groups is associated with high levels of engagement with e-learning courses. | Evolution of Facebook groups: Informal e-learning among medical laboratory scientists in Nigeria