The ease and speed with which we make a choice belies the complexity of the processes that underlie this ability. Each of our decisions integrates very diverse types of information: our current needs, perceptions, memories, social environment, and predictions about the future. How we process these distinct types of information may thus strongly influence our individual style and ability to make choices. In my research group, we study the neural mechanisms that determine this ability. We draw on choice theories from economics and mathematical psychology and employ a multimethod approach comprising behavioral experiments, computational modelling, neuroimaging, and brain stimulation methods. Our aim is to develop neurocomputational models of the brain processes that causally control our decisions. We hope that these models will contribute to a truly mechanistic understanding of human decision making, with far-reaching implications for economics (choice theory, mechanism design, policy making), the behavioral sciences in general, and medicine (behavioral symptoms of neurological and psychiatric diseases).