The pathways of precariousness, i.e., how or why unfavorable working conditions, such as fixed-term contracts or low-wage levels, are transformed into subjective experiences of precariousness, are not well understood. As these pathways affect mental and physical health and well-being, it is important to shed light on those phenomena, particularly in relation to psychological functioning. Although job insecurity is an important aspect of precarious work rightfully receiving significant research attention from the field of psychology, a more comprehensive psychological understanding of precarious work as a complex, dynamic, and multidimensional phenomenon is needed. This chapter focuses on key psychological theories and concepts of precarious work that have been developed specifically for this purpose: the subjective experience of work-related precariousness (SEWP), the work precarity framework (WPF), and the psychology of precarity (PoP). After introducing these concepts and frameworks, this chapter outlines the commonalities and unique contributions of each, integrating them into a comprehensive psychological perspective on precarious work. This perspective considers both micro (individual) and macro (structural) conditions that constitute precarious work, drawing attention to contextual aspects that convey the subjective experience of precariousness.