Completion of the genome sequence for an organism can produce a phase change in our understanding of both its function, and its evolution. The information gained is multiplied when closely

related species are sequenced in parallel. This special issue of Hereditycontains a set of papers on the genetics of three closely related parasitoid wasps from the genus _Nasonia_. These

papers are a first batch of genetic and population genetic analysis that have utilized these genome sequences, and tackle studies as diverse as recombination and neurotransmission, hybrid

breakdown and host preference. They highlight the new research avenues available in this emerging genetic model organism. Guest Editors: Professor Leo W. Beukeboom, University of Groningen,