That the Himalaya contain the basins of major rivers, regulate regional climate, and harbor rich biodiversity and varied ecosystems is well known. The perennial waters and biodiversity are closely linked to the livelihoods of over a billion people. The Himalaya are stressed because of a burgeoning human population and the escalating pressures of deforestation; urbanization; hunting; overexploitation of forests; and, more recently, intensive dam building. The cumulative effects of these forces have led to biotic extinctions and an increased frequency of hazards threatening human lives, livelihoods, and property. However, there is largely no comprehensive account of these challenges facing the Himalaya. We review and discuss the importance of the Himalaya and the need for their conservation by exploring four broad themes: (1) geobiological history, (2) present-day biodiversity, (3) why the Himalaya are worth protecting, and (4) drivers of the Himalayan change. We suggest scientific policy interventions, a strengthening of institutions, and proactive institutional networking to reverse the trend.