Critical Algorithmic Literacy explores the complexity of what it means to know algorithms and what such insight affords individuals, communities, and society. It suggests that critical algorithmic literacy involves understanding what algorithms do and why, but also what they mean to and for people as they navigate them in specific contexts. Drawing on a theoretical framework informed by feminist epistemologies, literacy studies, critical algorithm studies, and science and technology studies, the book illustrates how critical algorithmic literacy both shapes and is shaped by membership in different social worlds. Rather than as a value-neutral, universal skillset, it conceptualizes critical algorithmic literacy as relational, contextual, and socially situated. Through case studies of three communities entangled with algorithms in distinct ways, the book challenges prevailing visions of algorithmic literacy that privilege technical mastery and are driven by progress narratives serving powerful interests. It reorients critical algorithmic literacy around the goal of just social transformation, positioning it as a foundation for bottom-up governance. Kelley Cotter argues that critical algorithmic literacy plays an essential role in supporting individual agency and building collective momentum toward institutional action^—^but is a necessary, albeit insufficient, condition for broad scale change, given the structural power platforms continue to wield. In line with the broader participatory turn in governance, the book contends that governance of algorithms at the institutional level requires: 1) recognition of algorithm expertise as diverse and contextual; 2) de-centering of platform-centric knowledge; 3) centering heterogeneous, partial, and marginalized perspectives; and 4) embracing multi-layered, agonistic forms of public participation.