Gamification is a well-known approach that refers to the use of game design elements in information systems to make monotonous and tedious tasks more enjoyable. However, research and practice show that game design elements are oftentimes chosen and integrated in information systems randomly, therefore impeding the outcomes of such systems. In this regard, taxonomies can guide system developers, i.e., in selecting and combining game design elements to gamify their information system. Nonetheless, existing taxonomies do not provide such guidance for gamifying information systems. Therefore, the goal of our research is to consolidate the state of the art of gamification research and rigorously develop a gamification taxonomy. To achieve our goal, we conducted a systematic literature review and developed a taxonomy based on a rigorous taxonomy development process. We evaluate our theory by providing evidence of its feasibility with two practical cases: First, we show how the taxonomy helps to analyze existing gamification approaches, and, second, how the taxonomy guides to gamify information systems. Overall, we enrich theory by introducing a new taxonomy to better explain the meaning and characteristics of game design elements. Likewise, practitioners will be guided in selecting and combining game design elements for their gamification approaches.