The modern standard complete English edition is the 1997 Hackett "Plato, Complete Works", edited by John M. Cooper. For many of these translations Hackett offers separate volumes which include more by way of commentary, notes, and introductory material. There is also the "Clarendon Plato Series" by Oxford University Press which offers English translations and thorough philosophical commentary by leading scholars on a few of Plato's works, including John McDowell's version of the "Theaetetus". Cornell University Press has also begun the "Agora" series of English translations of classical and medieval philosophical texts, including a few of Plato's.