This book discusses various climate smart agro-technologies, their technical and economic feasibility across heterogeneous agro-climatic conditions, assessing farmers' willingness to adopt those technologies, impact of climate smart technology in agricultural production and possible policy and investment opportunities to upscale it. Containing eight chapters, the book starts with a discussion about the methodological aspects of priority setting of the farm technologies across various regions of South Asia including Eastern Indo-Gangetic plain, Western Indo-Gangetic Plain and arid regions. Using data from field based trials and expert solicitations, the book next deliberates on a list of feasible technologies, assessed by constructing climate smart Feasibility Index. Further on, there is an analysis, using stated preference method, of the behaviour of farmers in adopting climate smart technologies. Preference of women farmers has been given a special focus in this book. After discussing the method priority setting of the farm technologies, impact of climate smart technologies has been analysed using real time data. Government policies have been reviewed with the view of achieving climate smart agriculture in South Asia. The book also describes the optimization modelling framework for investment allocation and technology prioritization. The model integrates both the bio-physical and the economic optimization model to capture the agro-climatic heterogeneity within the region and the variability of technical feasibility across regions and crops. Results of this model will help policy makers to identify how much to invest, where to invest and what technologies to prioritize for investments.