Background: Previous research from the western world has highlighted the acceptability, feasibility, and effectiveness of school based mental health interventions in the developed countries. But very few research initiatives have happened in this direction from the low- and middle- income countries. It is important to understand the challenges in implementing school based mental health interventions and implement measures that could be developed to circumvent these challenges from low- and middle- income perspective. Novelty: The proposed research proposal (1) is a theory-driven study of implementation barriers; (2) occurs within a relevant real-world practice setting; (3) development of model based on implementation science and (4) involves interdisciplinary cooperation (public health, clinical, and education). Objective: The overarching objective of the proposed research proposal are to identify the challenges and opportunities existing within the school ethos in implementing evidence-based interventions to improve youth mental health and to identify the most appropriate implementation strategies for improving mental health among young people in schools in Chennai, a city in India, a low- and middle- income country. Methods: The proposed research project will be conducted in two schools in Chennai. A qualitative research methodology will be used to collect relevant data to understand the ethos of the school towards mental health and factors influencing them leading to the development of the whole school approach intervention Expected outcome: It is to understand the school ethos towards mental health and develop appropriate intervention to promote to mental health in schools.