Total quality management (TQM) research has concentrated on large firms. Little has been done on the TQM practices of small- to medium-sized enterprises (SMEs), particularly in developing countries. This paper investigates the relationship between TQM, planning behaviour and firm size by reviewing existing literature and collection of primary data from 54 SMEs in the Republic of Botswana. The findings indicated that the majority of SMEs understand the importance of both TQM and planning activities for their survival and growth. However, their approach to both is unsystematic, non-formal and short-term orientated. Both firm size and planning behaviour are found to have statistically significant relationships with TQM practices. As firm size increases from small to medium, and as SMEs move from operational to strategic planning, they attach greater degree of importance to TQM practices. However, the planning behaviour of SMEs is more strongly related to TQM practices as a prerequisite to the adoption of formalised TQM practices. Some implications for SMEs are also forwarded.