Sempervivum is a genus of monocarpic succulents in the family Crassulaceae, commonly known as Houseleeks. Other common names include Live-forever and Hen and Chicks. There are about 50 species and 4,000 named cultivars.

Sempervivums are with a wide range of colors of the leaves and the size and form of the rosettes. Their natural habitats are typically 3,000 to 8,000 feet (900 to 2,500 m) above the sea level, from Morocco to Iran, through the mountains of Iberia, the Alps, Carpathians, Balkan Mountains, Turkey, the Armenian mountains, to the northeastern part of Sahara and the Caucasus.

The genus with the first six species was described by Carl Linnaeus in the first edition of Species Plantarum in 1753.

The generic name "Sempervivum (sem-per-VEE-vum)" means "always (forever) alive." It is a compound of two Latin words, the adverb "semper," meaning "always," and "vivuvm," the neuter form of the adjective "vivus," meaning "alive," and refers to the plant's hardiness and durability.

The common name "Houseleek" refers to the growth of some species on the roofs in Europe, while "Liveforever" derives from the generic name and refers to their hardiness and durability. The common name "Hen and Chicks" comes from the appearance of the plants. The mature rosette "hen" produces offsets "chicks" around them or at the end of long stolons. As the "chicks" mature, they will also produce offsets, becoming a "hen" themselves. The common name, "Hen and Chicks," is shared with plants of other genera like Echeveria.