Centre for Mass Education in Science (CMES) is a national level voluntary development organization established in 1978 with an objective of taking the benefits of science and technology to the mass people of Bangladesh. The Basic School System (started in 1981) and Adolescent Girls Program (started in 1991) are the two major components of CMES programs. Since the beginning, the CMES program has evolved through continuous experimentation at field level and several replications elsewhere. What makes CMES unique is its holistic approach, starting with adolescent young boys and girls (age 12+), incorporating basic education up to class VIII level with technical skills training and livelihoods, and working with young women to fully manage operations themselves rather than relying on male relatives. This innovative model of CMES offers the disadvantaged adolescents and youths along with basic primary and secondary competencies and knowledge, practical technical and vocational skills training towards immediate enhancement in income and quality of life. CMES also strives to expand livelihoods options and provide non-traditional alternatives that help break gender stereotypes. CMES, being a dynamic organization, is always changing itself and its programs to make them contemporary and up-to-date based on continuous surveys, developing international standards and techniques, and needs assessment. CMES is serving the country through its 23 units over 20 districts of Bangladesh, centrally coordinated by it service center based in Dhanmondi, Dhaka.