The origin of this book is the compelling evidence that a high proportion of machinery-related deaths and injuries are attributable to genuine and serious risks originating within machine design and construction. This trend continues despite significant legal obligations, notably the European regulatory regime giving effect to the Machinery Directive (among others), and a substantial body of specialist knowledge originating in the disciplines of human factors and safety engineering. Grounded in empirical research with machinery manufacturers, this book aims to elucidate the factors and processes shaping firms' performance for machinery safety, and considers their compatibility with legal obligations. Through a unique blending of rich empirical data coupled with safety, human factors, socio-legal and learning scholarship, the book provides both a nuanced account of firms' performance for machinery safety, and makes conceptual and theoretical contributions to understanding and explaining their performance. Specifically, the book elucidates the role of knowledge and motivational factors - and how these are constituted - in shaping firms' performance. It reveals the multiple state and non-state influences that create plural responses among manufacturing firms, which typically operate in supply chains and networks, and often globally. These insights provide the foundations to enhance regulatory design, and the book's conclusion recommends some innovative directions for regulatory interventions to sustain the safe design and construction of machinery.