In a world that is increasingly aware of environmental challenges, architecture is presented as a powerful tool to address the preservation of the natural environment. The projects presented in this book show recent examples of the different ways in which architecture can contribute to meeting the challenge of preserving the natural environment. Through diverse strategies based on the promotion of energy efficiency, rationalisation in the use of natural resources, improvement of construction systems or respectful integration into the natural environment, this selection of projects reaffirms that architecture and sustainability are now indissoluble terms.