>Magister Scientiae - MSc / This thesis describes a multi-disciplinary collaboration towards iterative development of a mobile communication tool to support a Deaf person in understanding usage directions for medication dispensed at a pharmacy. We are improving usability and correctness of the user interface. The tool translates medicine instruction given in English text to South African Sign Language videos, which are relayed to a Deaf user on a mobile phone. Communication between pharmacists and Deaf patients were studied to extract relevant exchanges between the two users. We incorporated the common elements of these dialogues to represent content in a veri able manner to ensure that the mobile tool relays the correct information to the Deaf user. Instructions are made available for a Deaf patient in sign language videos on a mobile device. A pharmacy setup was created to conduct trials of the tool with groups of end users, in order to collect usability data with recorded participant observation, questionnaires and focus group discussions. Subsequently, pre-recorded sign language videos, stored on a phone's memory card, were tested for correctness. Lastly we discuss the results and implications of the study and provide a conclusion to our research.