Chapter 13 focuses on Luxembourg, which sits near the top of several regional and international indexes for ICT development, digital economy and society, and technological readiness, and hosts an impressive and growing number of data centres along with the regional or global headquarters of major internet and e-commerce players. The country’s small size, highly connected nature and financial strength translate into the active cooperation of service providers in criminal investigations in both domestic and cross-border situations. Drawing on interview-based research, this chapter provides an international audience with a targeted overview of the Luxembourg legal framework, the ways in which it has adapted to developments at the international and EU levels (Budapest Convention, European Investigation Order, Law Enforcement Directive) and the practical as well as legal challenges relating to the various forms of cooperation between service providers and law enforcement authorities. It offers a comprehensive, up-to-date picture of national data retention rules and discusses the potential impact of the new European Production Order on service providers in Luxembourg.