Many communities are facing serious solid waste disposal problems and considerable efforts are being made to reduce the quantities of municipal solid waste requiring disposal. Centralized composting of leaf and yard materials is gaining widespread popularity across North America in an attempt to divert these materials from landfill and process them into a valuable organic soil amendment for agricultural and horticultural purposes. To ensure the success of new centralized composting facilities, they must be adequately sized so that the incoming organic material can be suitably accommodated. This note presents a structured methodology for the sizing of centralized window composting facilities for leaf and yard materials, with land area requirements being determined for receiving, preprocessing, processing, and finishing operations. This approach may prove to be a useful tool to municipalities in the preliminary design of their centralized leaf and yard waste composting facilities.Key words: composting, municipal solid waste management, facility sizing.