Abstract Mental illness accounts for high levels of morbidity, mortality and poor quality of life among young people. Depression, anxiety, conduct issues and hyperactive disorder account for 13% of the global burden of disease that affects one in seven adolescents. In Kenya, not much is documented about the mental health of non-school-going adolescents, and yet they make up about 1.8 million of the country’s population. An ethnographic study by Focus Group Discussions with 32 rural northern Kenya Turkana-based adolescents divided into school and nonschool groups was conducted. We read out vignettes in which the main character exhibited symptoms of depression, schizophrenia or anxiety and explored their knowledge of causes and management options for the same, and then analyzed the data thematically. Participants described the conditions without referring to the local names we had collected earlier: depression (Akiyalolong), schizophrenia (waarit/Ngikerep) and anxiety (Ngatameta naaronok). They assigned curses, guilt, hunger pangs, and evil spells as causes, and believed friends and age-mates, parents, teachers, and the local chief, among others, could help, but rarely medical intervention. Interventions to improve the adolescent’s knowledge of mental illness are a much-needed support for the health of young people.