Portuguese public higher education institutions have been undergoing a major reform process since 2007. The most noticeable changes were introduced by Law 62/2007, which gave higher education institutions the option to choose between two different institutional models (foundational and public institute), and allowed the implementation of new government and management structures. We know, from the institutionalism theoretical perspective, that in a process of change institutions tend to be more similar than diverse. This study aims to analyse how Portuguese higher education institutions reacted to external pressures and reorganised their internal government and management structures. The main question it tries to answer is to what extent were institutions able to introduce more diversity in their organisational models? In order to find clues to answer this question, the study compares higher education institutions' internal structures by developing a qualitative study based on content analysis of internal legal documents from six universities (three that remain public institutes and three that have a foundational model).