SEYEDALIREZA FATEMI. Spatial interaction in Augmented Reality as a way to merge architecture and information. (Under the direction of Professor ERIC SAUDA)Nowadays huge amounts of information are transferred to people in architecture spaces. This information is generally presented either through different types of physical signage and environmental graphics or digitally through mobile or computer apps. However, existing methods are not sufficient to effectively communicate information in many different settings. Physical information is often not enough to dynamically communicate the vast amount of available information, while digital solutions such as mobile applications can disengage people from environments. In this thesis, I aim to address this real world problem by developing design solutions that afford communication of large amounts of information, while taking advantage of users movement through spaces.. To this aim, I develop Augmented Reality applications for museums that take advantage of users movement through spatial and proximity based interactions and dynamically communicate large amounts of information about objects. Specifically, the interface uses distance, orientation, and head angle of users towards objects as inputs for interaction. To evaluate the system, I conduct two consecutive user studies. First, a usability study that aims to understand the intuitiveness and discoverability of our proposed system as well as the proposed spatial interactions and second, a domain expert study to understand how receptive museum curators are to the idea of using such applications in real world settings. I find in general users easily interact with proximity and orientation based interaction, while they have issues in utilizing the head angle interaction technique. I also find that domain experts are very receptive of this system while they think a combination of spatial and direct interaction in the context of mobile Augmented Reality would be the ideal solution.