The sugarbirds are a small genus, Promerops, and family, Promeropidae, of passerine birds, restricted to southern Africa.

Using egg white proteins in the 1970s, Sibley and Ahlquist mistakenly placed them with the starlings (the samples used were actually those of sunbirds).

Molecular studies find support for few close relatives, and they are treated as a monotypic family at present,[4] although they form a clade with the Modulatricidae, three enigmatic African species formerly placed with the Old World babblers and thrushes.

[5][6] Both species have been shown to exhibit exceptionally high genetic diversity at both microsatellite and mitochondrial loci, with no signs of inbreeding and large effective population sizes.

The skull and tongue morphologies of the sugarbirds are very similar to that of the honeyeaters, the result of convergent evolution.

Nectar from the inflorescences of the Protea provide most of the energy these birds require, and they are considered significant pollinators of the genus.