The New York City Citizens' Commission on Planning for Enrollment Growth submitted a report on overcrowding in New York City schools that may serve as a guide to other cities striving to provide an effective education for ever-increasing numbers of students. Research on the impact of school overcrowding has been inconclusive, but there is some evidence that, especially in schools with a high proportion of students living in poverty, overcrowding can have adverse impacts on learning. It is unquestionable that it has a direct, and often severe, impact on the logistics of the school day. In cases where increases in school enrollment are expected to continue, the only guaranteed long-term means of relieving overcrowding is the expensive and time-consuming process of building new schools or of renovating and adding to existing schools. In cases where increases in enrollment may be temporary or where stop-gap measures are needed while new schools are being built, there are a number of short-term solutions. These strategies, in general, fall into two categories: (1) finding new space, whether through leasing, collaborative arrangements, relocating administrative space, or the district-wide redistribution of space, and (2) using time to use existing space more fully; extended-day and year-round programs are central to this effort. Adequate space for learning must be recognized as a fundamental educational necessity. (SLD)