Usability is one of the most important quality attributes in the new generation of software applications and computational devices. On the other hand, Model- View-Controller is a well known software architectural pattern and is widely used in its original form or its variations. The relationship between usability and the usage of Model-View-Controller, however, is still unknown. This thesis tries to contribute to this research question by providing the outcomes of a case study where a prototype has been developed in two different versions: one using Model-View-Controller and another using a widely known Object-Oriented guideline, the GRASP patterns. Those prototypes have been developed based on a non-functional prototype with a good level of usability. With the prototypes in hands, they were compared based on their design and based on the usability heuristics proposed by Nielsen. From this study, we discovered that the usage of MVC brings more advantages and disadvantages to the usability of the system than the ones that were found on the literature review. In general, the relationship between MVC and usability is beneficial, easing the implementation of usability features like validation of input data, evolutionary consistency, multiple views, inform the result of actions and skip steps in a process.