Tourist pressure on local populations, also termed 'overtourism', has received much attention in the global media, as tensions related to social, economic or environmental change have grown in many destinations. While protests against tourists and tourism development have existed for decades, these are now often more organised, vocal, and politically active. As a phenomenon associated with residents' negative views of tourism development outcomes, socio-psychological foundations of overtourism have so far been insufficiently considered. This paper summarises the historical background on crowding and attitudes of residents to tourism, to then discuss social psychological theories connected to place change in order to explain anti-tourism sentiment.