AbstractThis chapter deals with some methods and procedures developed and tested with specific entomopathogenic nematode strains as potential biological control agents. It is likely that for other species of nematodes, experimental conditions such as concentration, incubation period and incubation temperature may need to be optimized. The meal worm Tenebrio molitor has been suggested as an alternative model insect to Galleria mellonella for determination of nematode virulence. The bioassays described emphasize the potential of measuring quantitative behavioural responses as specific criteria for nematode virulence.