Program effectiveness of School Based Weekly Iron and Folic acid Supplementation (WIFS) in Urban setting – Mumbai Introduction: Various studies have shown efficacy of WIFS in school children which involves the evaluation of an intervention under ideal, controlled conditions. However effectiveness trials help determine if interventions can reliably be used under real-world conditions. Objective: To find the program effectiveness of school based WIFS in the urban setting in relation to the awareness of anaemia, perceived effects of the tablet, dietary practice, willingness to continue Weekly Iron and Folic Acid tablets and compliance to the tablet. Method: The cross-sectional, observational study was conducted in the 2013-14 academic year for class X students. Ethical committee approval was taken prior to the study. Out of total 317 students, 214 students gave consent for WIFS. After one year of WIFS, all the students of class X were interviewed with pre-tested questionnaire. Results: Awareness of anaemia was significantly high in those who consume WIFS as compared to those who did not consume WIFS. Perceived negative and positive effects were seen in 8.4% and 49.07% of the students respectively. Almost 70% of the students were willing to continue WIFS. Implementing supervised administration of Iron and Folic-Acid tablets during exam and vacation period was difficult. Due to this, mean compliance was 3 Iron and Folic Acid tablet / month. Conclusion: School based WIFS program in the urban setting may require few modifications in the operational guidelines in the program for its effectiveness