The library profession is now heavily involved in providing access to information through library web sites and it is a challenge to design a web site that has reliable content and a user interface that is intuitive to those who use it. As web accessibility and usability are major issues in the design of library Web sites, this paper suggests that the design will be most successful when a usability analysis tool is used throughout the design and redesign of academic library web sites. The research drew on the literature of Human-computer Interaction and usability engineering examining best practice usability and accessibility design guidelines. It identified those guidelines that were relevant to academic library web sites. In order to establish the extent to which Australian academic library web sites met usability guidelines a usability analysis tool was developed and used to evaluate a randomly selected sample of web sites. The web sites were categorised under higher education institutional archetypes as suggested by DETYA (1998) and the results were discussed in light of these groups. The research found that there was no correlation of the usability of the web sites between the archetypes. In fact the pattern of usability was randomly distributed across all institutions, with the best and worst results appearing in each archetypical category. The study concluded that the web has provided a whole new start for all institutions and after examining the results, it suggested that the design of early web sites was not based on the size or the past history of the institution that it belonged to, but rather reflected those factors, already established in the literature, that faced library web managers at that time, when designing the library web page.