The current logic of the market economy consists of extracting, producing, consuming and discarding. The efforts made to reduce the negative environmental impacts and promote recycling are not sufficient to offset the undesirable effects of this system described as "take, make and dispose. However, this linear approach to production and consumption, which prioritizes economic goals at the expense of environmental and social goals, has reached its physical limit. The negative effects caused by this model threaten not only the stability of economies, but also the integrity of ecosystems, which are essential for human survival. More than ever, companies are pressured to adopt more sustainable models derived from the intensification of certain trends, such as: the increasing dependence on fossil fuels; the poor management of natural resources; climate change, which is caused mainly by the increasing emissions of greenhouse gases; and the competitiveness featured by an ever expanding global market. These trends are in line with the European 2020 Strategy, which sets out a number of objectives designed to ensure within this time-frame a change in current models regarding the impact on natural capital. The circular economy defends the same principles of sustainability, and both share the same concerns. The circular economy aims to eradicate waste not just from manufacturing processes, but systematically throughout the life cycles and uses of products, and their components contributing to make organisations and the economy more sustainable. This book presents a scientific perspective about sustainability and the circular economy, describing different approaches, focusing on different sectors and exploring various methodologies. Welcome to the world of the circular economy and sustainability.