This chapter underscores the critical significance of acknowledging individual differences in psychological research to foster advancements in the field. By recognizing the existence of individual differences, we pave the way for uncovering essential general principles of behavior. A comprehensive examination of the interconnectedness between motivation and self-regulation sets the foundation for this study. Furthermore, this chapter delves into a detailed deconstruction of prevalent global constructs of self-regulation, elucidating their functional components. Through this functional analysis, a deeper understanding of the intricate processes influencing the interplay between motivation and self-regulation is attained. Particular attention is given to individual variations in the regulation of positive and negative affects, such as action versus state orientation. These distinctions hold paramount importance as they activate the mental systems necessary for actualizing intentions (action control) and embracing personal growth by learning from mistakes and painful experiences. By exploring these nuances of affect regulation, we shed light on the nuanced and personalized dimensions of self-regulatory competences. In conclusion, this chapter advocates for the integration of individual differences as a foundational element in psychological research, recognizing its role in propelling the field toward more comprehensive and nuanced explanations of human behavior and cognition.