ABSTRACT. Coccygomimus turionellae was found to possess a pre-ovipositional period of 3–6 days during which it ignored hosts. This period corresponded to the time needed for mature eggs to develop. Once oviposition began, the females exhibited host-feeding behaviour, using the nutrients for oogenesis. Host-deprived females were able to mobilize some body tissue in the production of eggs, but this resulted first in the loss of their flight ability and then in an increasing paralysis of their hind legs. Host-feeding varied from the females only sipping at the wound up to the female ramming her ovipositor around in the wound and/or chewing at the drill site. Wasps that only fed at the wound usually deposited eggs and those that had a high rate of host contact used the hosts mainly for oviposition. Wasps that had been without hosts showed a much greater tendency to feed, often destroying the hosts. The greatest preference for feeding was on hosts that were also highly preferred for oviposition. However, when less desirable beetle pupae were accepted, they were fed on to a larger degree than were the more ovipositionally desirable moth pupae. Host deprived parasitoids demonstrated an increased tendency to feed on hosts that are never naturally used for oviposition.