The A Stop Smoking in Schools Training (ASSIST) is a peer-led, school-based adolescent smoking prevention intervention proven to be effective not only in preventing smoking but also in promoting well-being and leadership skills among students. It uses the diffusion of innovation theory to address issues about smoking uptake in 13- to 14-year-olds. As this program has initially been tested in the United Kingdom, a study was conducted by the University of Glasgow (UK), De La Salle University (Philippines), and Gadjah Mada University (Indonesia) to test its feasibility in culturally different middle-income countries. This paper presents the results of a feasibility study conducted in the Philippines. The feasibility study examined whether ASSIST can be adapted in culturally different low- and middle-income countries and the extent to which it will be feasible. This presentation focuses on the process evaluation of ASSIST, examining the issues related to the acceptability of the intervention, from the consent process to the various data collection phases, and the training program