Book excerpt: This book presents the synthetic methodologies as well as the properties and potential usage of various ruthenium-containing materials. Starting from the first examples of 'ruthenopolymers' reported in the 1970s to the 3D architectures now synthesized, these materials have shown their importance far beyond fundamental polymer science. As well as highlighting the remarkable properties and versatile applications, this book also addresses a key question related to the applications of such heavy-metal-containing materials from the perspective of achieving a sustainable future. This book is of interest to both materials scientists and chemists in academia and industry.