Configuration management is all the rage. It’s pretty much acknowledged that no web sites of any size can be built without automation and configuration management. In reality, there are still many web sites built precariously by hand, held together with scripts and string. Yours might be one. Maybe recently you’ve seen the light and discovered config management tools and now you're going to automate ALL THE THINGS!
Hold your horse there cowboy! Let's think about and a level of self awareness required during the early days that you may not anticipate. A lot of these questions don't actually have yes/no easy answers. My major concern is to get folks thinking about things so they don't set up a chef server and go "now what" or in six months go "oh crap"