Continuum International Publishing Group / Bloomsbury Publishing
Developmentalism is a theory concerning the order of composition and the interpretation of Plato's dialogues. It is a modern phenomenon; ancient interpreters of Plato were ' unitarians' (Annas 1999:3-5; unitarians believe that there is a systematic unity of Platonic doctrine or belief among all the dialogues). There are several varieties of developmentalism; what is common to them all is the idea that the philosophical views contained in the dialogues, which are taken to reflect Plato's own views, changed significantly over time.
The Continuum Companion to Plato
Prior, W. J. (2012). Developmentalism. In G. Press (Ed.), The Continuum Companion to Plato (London: Continuum International Publishing Group), 288-289.