The first problem addressed here is our definition of the concept development-planning. The second problem is our definition of the disadvantaged today and in the future, that is, for whom is the planning effort directed. The third problem is the presentation of hypotheses and illustrations from various fields of activity, in order to demonstrate to ourselves and to others that our view and approach to the matter do indeed differ from existing ones. Development-planning is a rational, planned, comprehensive, and integrated effort to initiate and guide a process of systematic improvement of the educational system or parts of it. A study of the development of Israel's educational system reveals four major stages in the society's awareness of the problems of the disadvantaged in the past, and a fifth stage, which should shape the development of the educational system in the future on the basis of planning for the coming decade. The question, Who are the disadvantaged? should be raised in the context of seeing the condition of certain groups from the perspective both of expectations of the modernization stages and patterns and of the challenge and assistance offered by a system aimed at helping individuals and groups confront the expectation of survival and advancement. (Author/JM)