The aim of the present study was to introduce a general theoretical model of scientific competencies in higher education and to adapt it to three social sciences, namely psychology, sociology, and political science, by providing evidence from expert interviews and program regulations. Within our general model, we distinguished and specified four building blocks of scientific competencies: input, operations, and output, as well as personal characteristics. We defined "input" as content students are exposed to in their respective domains, "operations" as cognitive processes stated by Anderson et al. (2001), and "output" as content students create as a result of applying operations on input. We considered scientific competencies to be the constructive use of operations on input and the creation of output thereby. Furthermore, we considered personal characteristics that are relevant for competency acquisition and for working in a scientifically competent manner. In the present article we provide main results for the four building blocks of scientific competencies in psychology, sociology, and political science. Furthermore, we discuss limitations of our current model such as the necessity to determine criteria to further clarify what the constructive use of operations on input looks like in the different cycles of higher education.