Abstract
Current research on the quality of business process models mostly discusses the quality of a model mainly in terms of correctness of its behaviour. In this paper, we discuss another perspective: Because the main purpose of business process models is to be read and understood by humans, understandability is an important requirement. We present some patterns for improving the understandability by reducing the cognitive load. By applying these patterns to a repository of almost 1000 models, we have been able to improve the comprehensibility of several models.