The use of a focus group as a research method has become increasingly common in general practice related studies. Although existing guidelines for planning focus groups are very useful, a review of these guidelines indicate that a few of them are vague and need further elaboration. The authors review five existing guidelines for planning focus groups. These are size, number, duration, format and composition of a focus group. Suggestions have been made to address the uncertainties in these areas when a focus group is used. This paper was a section of manuscript presented at the 2nd International Qualitative Health Research Conference on 11 June 1994, Hershey, Pennsylvania.