Over the last decades, nanoscience and nanotechnology has been ascribed the potential to contribute beneficial applications in fields such as medicine, cosmetics, or environmental remediation. At the same time it is still contested whether engineered nanomaterials might be not one-sidedly "good" but may also entail negative side-effects for human health and the environment. To address this uncertainty, academic and political initiatives have sought to establish norms and practices to assess and govern nanomaterials. Rooted in different disciplines such as ethics, ecology, law, social and political sciences, the chapters in this edited volume explore the normative approaches, societal practices, and legal mechanisms which have emerged in the nano-field over the last two decades. The chapters also present a broad variety of evaluative approaches that may assist societal actors in their attempts to actively shape and contribute to the debate about nanomaterials.