Experienced Brachymeria intermediafemales are almost twice as likely to accept a Lymantria disparpupa as inexperienced parasitoids. The sequence of parasitoid behaviors that leads to host acceptance is highly canalized. Experienced parasitoids, however, have a higher probability of initiating host investigation and making a transition from drumming to grasping, which in turn almost invariably leads to ovipositor insertion. Experienced females found the host more quickly than inexperienced females. Host-handling time did not change with experience but was longer in females that accepted rather than rejected the host. Females exposed to gypsy moth odor but not contacting pupae behaved similarly to females that never experienced host-related stimuli.