International Medical Corps (IMC) started working in Sierra Leone in 1999 in response to the country’s civil war. It appears that they have now left Sierra Leone.
According to their website (accessed in 2016):
Between 1999 and 2008 they provided a broad range of emergency health care services to victims of the civil war in and refugees fleeing a similar conflict in neighbouring Liberia. Their work included primary health care, mental health, and HIV/AIDS programs. Following a two-year absence, International Medical Corps launched a five-year food security program in 2010 to prevent malnutrition in children under two years of age.
When the Ebola outbreak started they built upon existing relationships with communities and went house-to-house to teach families about the virus. As the outbreak intensified they ramped up their response to help curb the spread of the virus. They provided direct treatment to Ebola patients through three Ebola Treatment Centers (ETCs) and trained health care workers and other professionals in Ebola case management. These efforts were complemented by psychosocial support for patients, their families, and communities. In local hospitals and health facilities, they improved infection and prevention (IPC) standards and Ebola prevention and response mechanisms.