This thesis’ main objective is to investigate Sugden’s use of self-control in various parts of his work. Three lines of argumentation are pursued. In the first strand, I argue that Sugden’s (2017) method to identify self-control problems is identical to Frankfurt’s meta-desire theory. This definition of selfcontrol problems is inconsistent with the continuing agent in Sugden’s opportunity criterion (2004, 2010, 2018B, Sections 5-8), and Sugden’s interpretation of Hume’s decision theory (2006, 2021). The second strand reviews Sugden’s claim that people uncommonly self-acknowledge their self-control problems. This claim is assessed to be inadequately motivated. Following these two strands, I propose a new definition of self-control problems rooted in psychology and Pettit (2006). With an adaptation of the capability approach of Sen, the incapability approach, I argue that some opportunities can be restricted if people collectively suffer from self-control problems.