Alliaceae is a family of herbaceous perennial flowering plants. They are monocots, part of order Asparagales. The family has been widely but not universally recognised; in the past, the plants involved were often treated as belonging to the family Liliaceae, and still are by some botanists.
Note that quite a few of the plants that were once included in family Alliaceae are assigned to the family Themidaceae by both APG and APG II.
The most important genus is Allium, which includes several important food plants, including onions (Allium cepa), chives (A. schoenoprasum), garlic (A. sativum and A. scordoprasum), and leeks (A. porrum).
Michael F. Fay and Mark W. Chase. 1996. Resurrection of Themidaceae for the Brodiaea alliance, and Recircumscription of Alliaceae, Amaryllidaceae and Agapanthoideae. Taxon 45: 441-451 (abstract)