One of the things that I have really grown persnickety about is the placement of code. For example, I am a huge advocate that controllers in a rails project should read like a mini Domain Specific Language (DSL) and that as much logic as possible be delegated to the models. In my opinion the best way to do that in a Rails project is to learn the proper usage of ActiveRecord Association Extensions. You can check out the Rails API on this page and scroll down to the section called "Association Extensions" if you read the official docs. In short: