In my research I apply methods and models, developed in the natural sciences for the study of complex systems, within psychology in a non metaphorical way. In this talk I discuss a theoretical, a methodological, and a measurement example. The theoretical example concerns network models for general intelligence and attitudes. The methodological example concerns phase transitions in psychological processes such as cognition and multistable perception. The measurement example is based on Rekentuin.nl (Mathsgarden.com).