For the majority of software, development needs much longer than planned. Also, the big problems come up later when parts of an application need to be changed. Especially for web applications, quality assurance is a very sensitive topic: Developers need to carefully test and document their code, as well as the initial design must fit to coding standards. Using PHP, people can write very good software - but also do dramatically bad things. This session gives and introduction in quality assurance for PHP projects, including the planning and execution of tests using standarized methods. It covers all layers of a multi-tier web application with well-known tools, including PHPUnit, and includes a case study from a midsized media company that needed to rewrite almost their full code.