In 2003, the Basic Law of the Palestinian Authority (PA) was amended and a semi-presidential form of government was established. In January 2006, the legislative election resulted in a period of ‘cohabitation’ between the Hamas government and President Mahmoud Abbas from Fatah. In 2007, following the civil war between the two forces, governance structures in the PA all but collapsed. This article examines the extent to which cohabitation contributed to the problems of governance in the PA. We conclude that cohabitation did not determine the outbreak of conflict, but that it did contribute to the timing of the confrontation between the two actors.