Usability aspects of augmented-reality interfaces differ from the conventional desktop user interfaces and also from the usability of handheld mobile devices. In this course, we first review existing literature on usability considerations for the design of such interfaces. Then each participant, either individually or in small teams, designs and implements an augmented-reality user interface, after which we review methods for usability evaluation and particularly user experiments. Then, the participants design, carry out, and document a usability evaluation on their prototype, reporting their findings. It is recommended, although not mandatory, to participate in the seminar on Augmented Reality (58313306) in the Fall term 2013; other previous experience of AR-technologies will compensate for not taking the seminar. For the practical assignments, it is recommended to continue with the case studies of the seminar to save time on the prototype implementation.