The purpose of this note is to illustrate the importance of searching for resting tsetse when making a fly survey. Highly experienced entomologists and fly boys, who are accustomed to making surveys for G. palpalis (R.-D.), G. tachinoides Westw. and G. morsitans Westw., get into the habit of expecting tsetse to be attracted to themselves or to screens or to bait animals, and may easily fail to detect the less common species unless they appreciate that these should be searched for in their resting haunts.