Purpose – Personalization and the non-territorial office seem to be contradicting concepts. It is generally accepted that it is not possible to personalize workplaces in environments where no fixed individual workplaces are allocated. However, people seem to have a human need of personalization. Personalization can be done in different ways and for different reasons. Based on a literature review and a qualitative case study at a Dutch governmental organization, the purpose of this paper is to explain why and how personalization occurs in environments where non-territorial office concepts are introduced. Design/methodology/approach – Qualitative interpretative research design, in which literature study, document analysis, observations and talking, and interviews are combined, to understand the actor’s perspective and behavior in the non-territorial office of organization X. Findings – Conclusions of the study indicate personalization to be a relevant factor for consideration when implementing a non-territorial office design: when objects are prohibited to personalize your work environment, people seek several additional ways to make the environment familiar and comfortable for them and to mark their identity in the organization. Research limitations/implications – Access to organization X went via top management, which makes it possible that the position of the independent researcher was not clear to people. The research took place in three months, but not full time. Missing important behaviors is amongst possible consequences for the findings. Since this is one case study, further research is recommended. Practical implications – Balanced decisions and rules between organizational policy and human needs help the acceptance of own workplace lost in non-territorial offices. Originality/value – Personalization is a well-researched subject; as applied in non-territorial offices, it is not well researched yet. This research paper suggests that aspects of emotion and psychological need should be considered as well in the development of a non-territorial office.