After the Congresses of Grenoble (Creating an Atmosphere, 2008), Montreal (Ambiances in Action, 2012) and Volos (Ambiances, Tomorrow: The Future of Ambiances, 2016), this 4th International Ambiances Network Congress, entitled "Ambiances, Alloaesthesia: Senses, Inventions, Worlds" questions the renewal of the forms of feeling in a world that is undergoing major changes. It aims to consider how the contemporary environmental, social, technological, political and ethical changes are likely to affect the sensitive worlds, their ambiances, and the ways of experiencing them. This conference brings together more than a hundred scientific contributions coming from an international base of academics, practitioners, artists and PhD students working on ambiances and atmospheres. They offer an up-to-date account of the variety of themes and issues within this field, showcasing the latest research and methodological approaches. Organized in sixteen themed sessions, the presentations examine the ongoing preoccupations, debates, theories, politics and practices of this field, drawing on multidisciplinary expertise from areas as diverse as anthropology, architecture, computer science, cultural studies, design, engineering, geography, musicology, psychology, sociology, urban studies and so on. The 4th International Congress on Ambiances focuses on the renewal of the forms of feeling in a world that is undergoing major changes. Composed by “allo” which stands for “other, of another kind”, using the term alloaesthesia aim to characterize: other senses, or senses of another kind, and suggests to be comprehensive of the emergence of potential new kinds of senses and sensibilities. This Congress aims to consider how the contemporary environmental, social, technological, political and ethical changes are likely to affect the sensitive worlds, their ambiances, and the ways of experiencing them. How these changes question the research on ambiances and atmospheres, at epistemological, theoretical, methodological and practical levels?