The goal of the research is to evaluate the usability of the structural navigation, also known as Breadcrumb Trail. This tool shows the path back to the pages previously visited by users, allowing them to link back to major categories of information. There are several different types of Breadcrumbs and efficiencies will be evaluated. The hypothesis affirmed that the structural navigation helps users browse and execute tasks faster, also providing some information such as where the users are located within the site. For that hypothesis to be verified, a research methodology has been adopted involving on-line questionnaires and usability tests. However, for developing a more complete work, in order to contribute for the improvement of Internet projects in Brazil, the first chapters were dedicated to subjects related to the Human-Computer Interaction and Usability issues. After this survey, a field research has been made so that the Breadcrumbs could be evaluated in terms of function and visual presentation. For the accomplishment of the usability tests, a prototype has been developed based on the Brazilian Central Bank`s website. The tests, wich counted with 67 volunteers, had been created in the Globo.com Usability Lab. The volunteers were chosen by the use of an on-line form. The results were acceptable, even though the Breadcrumb navigation was efficient in some situations and inefficient in others. The results has been generalized by the creation of six guidelines for using the element.