Originally published in Italian in 2010, this book is the first to address the theory of atmospheres in a thorough and systematic way. It examines the role of atmospheres in daily life, and defines their main characteristics. Outlining the typical phenomenological situations in which we experience atmospheres, it assesses their impact on contemporary aesthetics. It puts forward a philosophical approach which systematises a constellation of affects and climates, finds patterns in the emotional tones of different spaces (affordances) and assesses their impact on the felt body. It also critically discusses the spatial turn invoked by several of the social sciences, and argues that there is a need for a non-psychologistic rethinking of the philosophy of emotions. It provides a history of the term 'atmosphere' and of the concepts anticipating its meaning (genius loci, aura, Stimmung, numinous, emotional design and ambiance), and examines the main ontological characteristics of atmospheres and their principal phenomenological characteristics. It concludes by showing how atmospheres affect our emotions, our bodies' reactions, our state of mind and, as a result, our behaviour and judgments. Griffero assesses how atmospheres are more effective than we have been rationally willing to admit, and to what extent traditional aesthetics, unilaterally oriented towards art, has underestimated this truth.