Sempervivoideae is the largest of three subfamilies in the Saxifragales family Crassulaceae, with about 20–30 genera with succulent leaves.

Unlike the other two smaller subfamilies, which are highly derived, Sempervivoideae retain the basic features of the family Crassulaceae.

[6] The Telephieae[b] genera consist of former infrageneric taxa of Sedum, and are distributed primarily in East Asia, but with a few species found in Europe and N America (Hylotelphium).

Defined by 5-merous flowers, free petals, flat, dentate leaves and tuberous roots or thickened rhizomes.

[6] The second is the genus Umbilicus with about 13 species, distributed in the Mediterranean, Macaronesia, SW Asia, Arabia and north to east Africa.

[6] These genera are among those that have been segregated from Sedum, including:[3] The phylogenetic relatpionships of the Petrosedum clade are not fully resolved, and hence is unplaced, due to discordance in molecular marker analyses.

Earlier treatments considered Jovibarba a section of Sempervivum[3] but has subsequently been demonstrated to be a separate genus.

[6] Aeonieae (also referred to as the GAMA clade, for Greenovia, Aeonium, Monanthes and Aichryson),[15] whose distribution is primarily Macaronesia, have polymerous flowers, and include genera derived from within Sedum.

However Monanthes and Aeonium appear not to be monophyletic;[6] Sedeae is the largest tribe of these and has been considered as consisting of two sister clades, Leucosedum and Acre.

[6] Given the monophyly demonstrated for Aeonieae and Semperviveae (as quite distinct from Sedeae), it has been recommended that those species of Sedum originally found in those tribes, be removed from the genus and reassigned.

This includes Sedum series Rupestria from Semperviveae, but collectively account for only a small fraction of the genus.

While restricting Sedum to Sedeae simplifies the infrafamilial structure of the genus, its species remain distributed within both clades of this tribe.

The Sempervivoideae subsequently dispersed north to the Mediterranean region, and from there to Eastern Europe and Asia (Sempervivum and Leucosedum clades), with multiple groups spreading over the three continents of the Northern Hemisphere.

Two lineages from the European Crassulaceae eventually dispersed to North America and underwent subsequent diversification.