Critical review of the existing knowledge on livelihoods, poverty and vulnerability in the Hindu Kush Himalaya (HKH). The characteristics of mountain areas (referred to in the chapter as ‘mountain specificities’) uniquely condition the lives and development of people. While inaccessibility, fragility, and marginality act as constraints on development, the abundant biological diversity, ecological niches, and adaptation mechanisms present windows of development opportunities for mountain people. Mountain specificities need a distinct frame of analysis from what is used in the lowlands.