The issues of reliability and validity in qualitative research are not as readily codified as has been the case for quantitative research. However, a variety of methods do exist and are reviewed here. This general review is followed by a detailed illustration of selected techniques, including the use of counting in qualitative research, the development of systematic coding schemes with the aid of computer programmes, searching for deviant cases and the use of the transcription techniques of conversation analysis. The examples given are drawn from a variety of studies conducted by the authors.