The question of how to achieve effective levels of tsetse fly control at financially and environmentally acceptable costs is perennial and contentious. Even though tsetse flies are slow to reproduce, populations seem to recover sooner or later after control measures are relaxed. A great capacity and propensity to disperse is said to be characteristic of tsetse flies, and many experts suggest that area-wide control measures and eradication are unobtainable for this reason alone. Others contend that area-wide methods, including the sterile insect technique, can be used successfully to achieve a high degree of control. Can a study of tsetse fly population genetics add anything to the ongoing debate? I believe it can. Here’s why.