This Forum discusses the significant growth of international large-scale assessments (ILSAs) since the mid-1990s. Addey and Sellar's contribution ("A Framework for Analysing the Multiple Rationales for Participating in International Large-Scale Assessments") outlines a framework of rationales for participating in ILSAs and examines the multiple localised meanings attached to ILSA participation. This framework is discussed under seven headings: (1) evidence for policy; (2) technical capacity building; (3) funding and aid; (4) international relations; (5) national politics; (6) economic rationales; and (7) curriculum and pedagogy. It shows how ILSAs can serve multiple purposes--a flexibility that has contributed to the rapid growth of the phenomenon. Steiner-Khamsi ("Focusing on the Local to Understand Why the Global Resonates and How Governments Appropriate ILSAs for National Agenda Setting") focuses on the local to understand why the global resonates and discusses how governments appropriate ILSAs for national agenda setting. Lingard (International Organisations' Rationales for Large Scale Assessments") examines the rationales of international organisations and the contribution of media coverage to the increasing significance of ILSAs. Finally, Verger ("Theorising ILSA Participation") theorises rationales for ILSA participation according to three frames for understanding global education policy: rationalism, neo-institutionalism and political economy approaches.