This Element examines the notion of content-independence and its relevance for understanding various aspects of the character of law. Its task should be understood expansively, as encompassing both inquiry into that which makes law into what it is, and inquiry into what law ought to be, which values it ought to serve, and which aspects of its character may play a facilitative role in law realising aspects of its potential. Many existing discussions of content-independence focus largely on the justificatory aspects of content-independence: whether, and, if so, how, there can be content-independent reasons for action, or content-independent justifications of rules, or the extent to which political obligation is content-independent. This Element, too, examines such issues but also seeks to explore an additional possibility: that the notion of content-independence can illuminate issues regarding law's existence, identification, and systematicity.