This study examines how Design principles affect the view of Usability in Agile development. This case study has been conducted together with Uppsala Municipality’s Development department. The Design principles from Användningsforum and Government Digital Service are studied together with Agile development strategy to determine the influence on Usability. This is an empirical inductive study where data is collected and analyzed so that a theory may be presented. The thesis is based on qualitative data gathered from Uppsala Municipality’s development project and focus on the experience and attitude of the developers in the department. Data is collected through interviews and observations of the team members. Data is analyzed with Grounded theory approach. From the results it is concluded that the Design principles influence members of the department's awareness and focus on Usability when work with Agile development project.