In the South African context, "impact" is one of those words that has gathered a set of layered meanings in the field of research and evaluation. It is generally used to mean the "effect" an activity or experience has had on its target audience. Has the experience changed things in any way? Has it made a difference? This paper explores what is meant by "impact" in different contexts and will examine some of the results of the theatre and drama projects with young people presented by DramAidE (Drama for AIDS Education). I refer to the concept "applied theatre" meaning the practice of drama and theatre-based activities outside the formal school curriculum and traditional theatre buildings. In South Africa, applied theatre is an important tool in the field of health and environmental education for young people. This paper argues that impact assessment has shown that both drama workshops and public performances can provide education and information and prompt young people to take action thus bringing about social change. (Contains 9 notes and 1 figure.)