Fleas were collected from 60 dogs and 32 cats living in south west England. Ctenocephalides felis felis and Ctenocephalides canis were found on both dogs and cats, with a marked preponderance of C felis felis on both species. More female fleas than males were found. There was no apparent tendency for C canis to be found more often in rural areas than in suburban areas. The survey confirmed the polyxenous nature of both species of flea. The significance of this state is discussed in relation to flea control, and the author concludes that it is unlikely that all significant flea species could be completely eliminated from the environment of pet animals.