Many OECD countries have undergone reforms over the past decade to introduce advanced roles for nurses in primary care to improve access to care, quality of care and/or to reduce costs. This working paper provides an analysis of these nurse role developments and reforms in 37 OECD and EU countries. Four main trends emerge: 1) the development in several countries of specific advanced practice nursing roles at the interface between the traditional nursing and medical professions; 2) the introduction of various new, supplementary nursing roles, often focused on the management of chronic conditions; 3) the rise in educational programmes to train nurses to the required skills and competencies; and 4) the adoption of new laws and regulations in a number of countries since 2010 to allow certain categories of nurses to prescribe pharmaceuticals (including in Estonia, Finland, France, Netherlands, Poland and Spain).