In a lengthy two part interview lead designer Chris Avellone and “second designer” Chris McComb talk about developing the game Planescape: Torment at Black Isle Studios. The interview can be found at RPGWatch
At the end of the second page Chris Avellone shares the original Vision Statement for this game. This document was used to Pitch the game to their management. With quotes like “don’t do what’s been done” and “re-examine your first instinct” it’s an interesting read.