Managed entry agreements are a set of instruments used to reduce the impact of uncertainty and high prices when introducing new medicines. This study develops a conceptual framework for these agreements and tests it by exploring variations in their implementation in Belgium, England, the Netherlands and Sweden and over time as well as their governance structures. Using publicly available data from HTA agencies and survey data from the European Medicines Information Network, a database of agreements implemented between 2003 and 2012 was developed. A review of governance structures was also undertaken. In December 2012 there were 133 active MEAs for different medicine-indications across the four countries. These corresponded to 110 unique medicine-indications. Over time there has been a steady growth in the number of agreements implemented, with the highest number in the Netherlands in 2012. The number of new agreements introduced each year followed a different pattern. In Belgium and England it increased over time, while it decreased in the Netherlands and fluctuated in Sweden. Only 18 (16%) of the unique medicine-indication pairs identified were part of an agreement in two or more countries. England uses mainly discounts and free doses to influence prices. The Netherlands and Sweden have focused more on addressing uncertainties through coverage with evidence development and, in Sweden, on monitoring use and compliance with restrictions through registries. Belgium uses a combination of the above. Despite similar reasons being cited for managed entry agreements implementation, only in a minority of cases have countries implemented an agreement for the same medicine-indication; when they do, a different agreement type is often implemented. Differences in governance across countries partly explain such variations. However, more research is needed to understand whether e.g. risk-perception and/or notion of what constitutes a high price differ between these countries.