Current criticism of theoretical psychology concerns, in particular, the state of its foundations and the construction of theories, while the evolution of the discipline leads to its disunity. According to one of the points of view discussed, psychological knowledge must be unified in order to overcome theoretical fragmentation. Those who are concerned about the lack of a unified theory in psychology explore various aspects of disunity and the possibility of unifying theoretical psychology. In recent decades, a number of approaches to unification have been developed, and now theoretical studies of unification need to be harmonized. I believe that in order to develop a solid framework, it makes sense to reach a consensus on the general, conceptual and methodological ideas of unification. On this basis, it would be possible to develop a program for creating an approach to unification in theoretical psychology, and I propose an outline of three possible ones.