Since its increase in popularity over the last 10 years, Airbnb has been at the centre of many discussions of its possible negative externalities on cities regarding housing stress, mainly focusing on its effects on gentrification and relocation of residents. The final aim of this thesis is to analyse if there is any correlation between rent and house prices increases and the density of Airbnb over the last few years, using the case study of Firenze, one of the most visited and most loved cities by tourists in Italy.