The Maasai (sometimes spelled "Masai" or "Masaai") are a Nilotic ethnic group of semi-nomadic people located in Kenya and northern Tanzania. They are among the best known of African ethnic groups, due to their distinctive customs and dress and residence near the many game parks of East Africa. They speak Maa (ɔl Maa), a member of the Nilo-Saharan language family that is related to Dinka and Nuer, and are also educated in the official languages of Kenya and Tanzania: Swahili and English. The Maasai population has been reported as numbering 453,000 in Kenya in the 2009 census, compared to 377,000 in 1989 and 400,000 in 2000.

The Tanzanian and Kenyan governments have instituted programs to encourage the Maasai to abandon their traditional semi-nomadic lifestyle, but the people have continued their age-old customs. Recently, Oxfam has claimed that the lifestyle of the Maasai should be embraced as a response to climate change because of their ability to farm in deserts and scrublands. Many Maasai tribes throughout Tanzania and Kenya welcome visits to their village to experience their culture, traditions, and lifestyle.