After implementing changes in language arts instruction, the principal--who is in a key position to sustain or institutionalize the changes--faces several responsibilities. Factors involved in directing innovations to become "built in" to school programs include solving specific problems, sharing decision-making responsibilities, upgrading and updating staff competence and commitment, making organizational changes, preventing threats to long-term success, and adapting important factors to school settings. Since most innovations are considered in the context of remedying school problems, educators should determine the nature of local problems. Britain's success with the open classroom concept, for example, was inappropriate for American inner-city school systems. Sustaining a program involves efforts that are relevant to different school settings, which has been demonstrated by Miles (1983) in a study of 12 elementary and secondary schools. Environmental fluctuations--budget cuts and declining student enrollment--and educator job mobility can threaten the long-term quality of innovations. Preventive strategies include protecting against budget cuts and providing opportunities for individuals to share their competence. Strong leadership, particularly at the middle management level, is vital in carrying out durable language arts innovations. (CJH)