This paper clearly sets out what is meant by the term "normalisation" (social role valorisation). It quotes the very personal terms of interpretation used by Nirje,who first gave prominence to the term in the late 1960s and crystallised it into a principle , and Wolfensberger, Director of the Training Institute for Human Service Planning and Change Agentry at Syracuse University. Wolfensberger describes his work at converting the early formalisations of Nirje into a scientific theory . The paper describes what normalisation means to people who have disabilities in their everyday life. Keywords: Social Role Valorisation, Theory