Lysophosphatidic acid (LPA) is a serum-borne phospholipid that activates a specific G protein coupled receptor to evoke multiple cellular responses. Recent work has identified two cDNAs encoding putative LPA receptors, Various LPA-like agonists that act on distinct receptors, and new pathways that link the receptor(s) to such diverse events as Ras signalling, cytoskeletal remodelling and membrane depolarization.