Mountain agriculture is more vulnerable to adverse impacts of climate change as it heavily relies on rainfall. Although the impact of the climate change on agriculture and food security has become a serious concern, so far limited efforts have been made to understand how climate change impacts food security of the mountain communities of the HKH region, how poor households adapt to changing conditions, and what options are available to facilitate better adaptation. The nature and causes of agriculture and food security in mountains is quite different from the plains and require a specific set of policy measures. This chapter aims to provide a better understanding of the vulnerability of mountain agriculture and food security to climate change risks. It analyses the appropriateness of existing policies and programmes for mountains, policy and local level adaptation trends, areas of adjustments, and possible adaptation options such as climate smart agriculture, rainwater harvesting technologies, solar energy for irrigation, and better crop choices based on agro-ecological potential of specific areas conducive to improved food and livelihood security in the mountains. One of key questions that arises in the chapter is “How can the poor and marginalized mountain farmers be included in the adaptation process?”