Host-parasitoid interactions are among the most studied interactions between invertebrates
because of their fundamental interest - the evolution of original traits in parasitoids
- and applied, parasitoids being widely used in biological control. Immunity, and
in particular cellular immunity, is central in these interactions, the host encapsulation
response being specific for large foreign bodies such as parasitoid eggs. Although
already well studied in this species, recent data on Drosophila melanogaster have
unquestionably improved knowledge of invertebrate cellular immunity. At the same time,
the venomics of parasitoids has expanded, notably those of Drosophila. Here, we summarize
and discuss these advances, with a focus on an emerging "time-dependent" view of interactions
outcome at the intra- and interspecific level. We also present issues still in debate
and prospects for study. Data on the Drosophila-parasitoid model paves the way to
new concepts in insect immunity as well as parasitoid wasp strategies to overcome
it.