TRANSLATIONS:
The version in 4 volumes by Jowett (Oxford) is the standard. It contains good introductions.
The Republic has been translated by Davies and Vaughan.
Two volumes in the Loeb Series have appeared.
A new method of translation of Plato is needed. The text should be clearly divided into sections; the steps of the argument should be indicated in a skeleton outline. Until this is done study of Plato is likely to cause much bewilderment.
Plato and Platonism, by Pater, is still the best interpretation of the whole system.