Approximately one-third of the developing world’s population does not have regular access to essential medicines—medicines defined by the World Health Organization as necessary for satisfying the primary health care needs of a population. For countries in sub-Sarahan Africa (SSA), a particular challenge is improving access to essential medicines for mental, neurological, and substance use (MNS) disorders. Reducing the cost, increasing the supply, and ensuring the quality of these medicines has the potential to significantly improve the lives of patients with MNS conditions.