This paper describes the introduction and continuing evolution of Direct Instruction programmes in Language, Reading and Arithmetic, in a School for developmentally delayed children in an institutional setting. An account is given of: the reasons for adopting Direct Instruction as a teaching method; staff training before and since the introduction of the system; detailed planning and implementation of the programmes; immediate results within the first six months; assessment procedures; and reactions by staff and outside observers. Cognitive and intellectual development achieved after two and a half years is analysed with the help of research data and audiovisual materials. This demonstrates a significant narrowing of the gap between ‘normal’ and ‘retarded’ functions and points to some likely longer term implications.