In the metropolitan area of Colombo, Sri Lanka, the issue of municipal solid waste management moved to the center of political attention in April 2016 when the accumulated waste mountain of a centralized dumpsite in Meethotamulla, situated at the periphery of the city region, suddenly collapsed. In this context, this particular working paper aims to analyze the institutional architecture of waste governance in Sri Lanka with special attention paid to two selected municipalities, namely Dehiwala-Mt. Lavinia and Boralesgamuwa, for the purpose of obtaining a comprehensive understanding of the functions, responsibilities and the nature of the relationship between different actors.