Tenwek Hospital is one of the largest mission hospitals in Africa. Tenwek is located in the Western Highlands of Kenya, 240 kilometers (150 miles) from Nairobi in the Bomet District of Kenya's Rift Valley Province. It provides primary health care to 600,000 Kipsigis people within a 32 kilometer radius and serves a referral center for a much larger region. Surrounding Tenwek are several small government dispensaries and health centers; many patient referrals come from those facilities.

Many ethnic groups utilize Tenwek Hospital. The dominant ethnic group near Tenwek is the Kipsigis. Not far away are the Kisi and Maasai. The Maasai are notable because they have been slower to assimilate many elements of culture and language used elsewhere within Kenya, including western influences on African culture. Both the Maasai and the Kipsigis have an emphasis on animal husbandry (cattle), but the Kipsigis have adapted more to a residential/agricultural lifestyle than have the Massai who are more nomadic.

The Tenwek area of Bomet District has a population density of 216 people/sq. kilometer. The people speak Kipsigis but both Kiswahili and English are becoming more and more widely used. The main industries of the area are agriculture and animal husbandry. The principal food crop is maize (corn). Potatoes, beans, and cabbage are abundant also, and cash crops include tea and pyrethrum. Most of the small farms have cattle, goats, or sheep and poultry in addition to the crops.