The thesis is nested within a larger research programme in India which developed a suite of low-intensity psychological interventions for addressing common mental health problems among school going adolescents in low income urban communities in India – PRIDE (PRemIum for aDolEscents, 2016-2022 (Sangath, 2017)) at Indian’s leading not for-profit, non-governmental mental health research organization, Sangath. Chapters 2-6 summarise the studies included in this thesis. Chapter 2 presents a summary of salient context-specific factors that influence stress and coping among school-going adolescents based on focus group discussions undertaken with 191 school-going adolescent boys and girls aged 11-17 years (New Delhi and Goa). Salient social stressors included academic pressure, difficulties in romantic relationships, negotiating parental and peer influences, and exposure to violence and other threats to personal safety. Additionally, girls highlighted stress from having to conform to normative gender roles and in managing the risk of sexual harassment, especially in Delhi. Adolescents primarily used emotion-focused coping strategies (e.g., distraction, escape-avoidance, emotional support seeking). Problem-focused coping (e.g., instrumental support seeking) was less common. Examples of harmful coping (e.g., substance use) were also reported. Chapter 3 summarizes the views of diverse stakeholders (New Delhi and Goa) about their priorities and preferences for SBMHS. Semi-structured interviews and focus group discussions were conducted with adolescents (n=191), parents (n=9), teachers (n=78), school counsellors (n=15), clinical psychologists/psychiatrists (n=7) across the two sites. All stakeholders indicated the need for and acceptability of SBMHS. Adolescents prioritized resolution of life problems. Parents and teachers however, emphasized functional outcomes. Problem solving was suggested as a component of SBMHS. Face-to-face counselling and practical guidance was preferred while self-help was less frequently endorsed. Concerns about confidentiality were raised. Structured sensitisation was recommended to promote adolescent’s engagement. Chapter 4 outlines the detailed protocols of evaluation of the sensitisation interventions and the first-line problem solving interventions in the school settings in New Delhi through interlinked randomised controlled trials. The effects of the classroom-based sensitisation intervention involving a brief video presentation and moderated group discussion on the demand for counselling services (Intervention Condition, IC) over and above the whole-school sensitisation interventions (Control Condition, CC) were evaluated through an embedded recruitment trial which adopted a stepped-wedge, cluster randomized controlled trial (SWCRCT) design involving 70 classes that were randomly selected across grades 9th-12th in six Government-run secondary schools in Delhi (Trial registration number: NCT03633916). Chapter 5 includes the findings of this trial. Between 20 August 2018 and 9 December 2018, 835 students (23.3% of all students) were referred into the host trial. The proportion of students referred was significantly higher in the IC (IC=21.7%, CC=1.5%, OR=111.36, 95%CI 35.56 to 348.77, p