The law of unilateral acts and the law of treaties are generally considered to be two distinct areas of international law. While the former governs the effect of unilateral undertakings by States, the latter governs, inter alia, the formation, interpretation, termination, and suspension of treaties. In 2011, the International Law Commission (ILC) concluded a two-decade study on reservations. One of its most remarkable insights is the argument that reservations ought to be considered ‘unilateral acts’. Thus, certain rules pertaining the law of unilateral acts ought to apply to reservations. This article critically examines the ILC's novel proposal as well as its attempt to provide answers to contemporary questions on reservations through conceptualizing reservations as unilateral acts.