This document summarizes research on common mistakes made when modeling business processes using BPMN notation. 15 process modeling "anti-patterns" were identified through analysis of student-designed process models from 2002-2007. Each anti-pattern is described, including potential impacts and proposed solutions. The most common anti-patterns involved improperly connecting elements, such as activities not being connected within a pool or sequence flows crossing process or pool boundaries. The research aims to improve process modeling education and tools to prevent such mistakes and improve model quality.