© 2017 Fundacion Infancia y Aprendizaje. The personalization of space is constructed through the items that the resident distributes around the space they inhabit, and they can be considered part of the resident’s self. Three studies were conducted with the goal of establishing the categories into which the objects contained in bedrooms can be organized and to evaluate to what extent these categories are related to the extended self and attachment. In the first study, with 77 students, we obtained a list of the most representative objects in their bedrooms. In the next study, a group of 56 students classified these objects freely using their own criteria; a subsequent cluster analysis showed four categories: Functional, Personal Grooming, Symbolic and Free Time. In the last study, 144 students evaluated the relationship between the categories of the objects and the extended self and attachment. The results showed that the residents’ representative objects were part of their extended self more than the level of attachment attributed to these objects.