AbstractKelly repertory grids (Kelly, 1955), and associated computer programs (Shaw, 1980) were used to evaluate the effectiveness of the Post Experience Diploma in Literacy Development taught at Middlesex Polytechnic. Thirteen teachers participated in the study and they reported two major causes of change directly attributable to the Diploma. These were: (a) a greater knowledge, and (b) increased self‐awareness. The two causes of change were closely related to the stated aims and objectives of the Diploma and they instigated many positive outcomes related to: (i) the organisation and planning of the teaching of reading, (ii) the nature of communication and interaction with colleagues, and (iii) specific child centred benefits. Fewer negative outcomes were reported but they should provide the course tutors with a feedback to re‐direct their energies more profitably to overcome these problems when next teaching the Diploma. It is suggested that senior personnel in the schools provide conditions for the returning teacher which enable the potential benefits of gaining a Diploma to be maximised within the sch