Between 2012 and 2017, the U.S. President's Malaria Initiative-funded MalariaCare project supported national malaria control programs in sub-Saharan Africa to implement a case management quality assurance (QA) system for malaria and other febrile illnesses. A major component of the system was outreach training and supportive supervision (OTSS), whereby trained government health personnel visited health facilities to observe health-care practices using a standard checklist, to provide individualized feedback to staff, and to develop health facility-wide action plans based on observation and review of facility registers. Based on MalariaCare's experience, facilitating visits to more than 5,600 health facilities in nine countries, we found that programs seeking to implement similar supportive supervision schemes should consider ensuring the following: 1) develop a practical checklist that balances information gathering and mentorship; 2) establish basic competency criteria for supervisors and periodically assess supervisor performance in the field; 3) conduct both technical skills training and supervision skills training; 4) establish criteria for selecting facilities to conduct OTSS and determine the appropriate frequency of visits; and 5) use electronic data collection systems where possible. Cost will also be a significant consideration: the average cost per OTSS visit ranged from $44 to $333. Significant variation in costs was due to factors such as travel time, allowances for government personnel, length of the visit, and involvement of central level officials. Because the cost of conducting supportive supervision prohibits regularly visiting all health facilities, internal QA measures could also be considered as alternative or complementary activities to supportive supervision.