Do you regularly deliver code that nobody else has seen? Does anyone even know your production code, or has everyone forgotten what it did? Code review is one of the most interesting and unknown practices in software development. It is the cheapest way to reduce errors, increase ownership of the codebase and train the team, all at once! In this talk we will see an update with numbers and references to convince you and your bosses to implement reviews as a crucial step in your development process.