The superfamily Ichneumonoidea contains one extinct and three extant families, including the two largest families within Hymenoptera: Ichneumonidae and Braconidae. The group is thought to contain as many as 100,000 species, many of which have not yet been described. Like other parasitoid wasps, they were long placed in the "Parasitica", variously considered as an infraorder or an unranked clade, now known to be paraphyletic.

The Ichneumonidae, also known as ichneumon wasps, ichneumonid wasps, ichneumonids, or Darwin wasps, are a family of parasitoid wasps of the insect order Hymenoptera. They are one of the most diverse groups within the Hymenoptera with roughly 25,000 species described as of 2016. However, this likely represents less than a quarter of their true richness as reliable estimates are lacking, along with much of the most basic knowledge about their ecology, distribution, and evolution. It is estimated that there are more species in this family than there are species of birds and mammals combined. Ichneumonid wasps, with very few exceptions, attack the immature stages of holometabolous insects and spiders, eventually killing their hosts. They thus fulfill an important role as regulators of insect populations, both in natural and semi-natural systems, making them promising agents for biological control.