Strengthen the skills and supports for school leaders. Costa Rica should use the results of its school leader tests to improve the relevance of initial and in-service leadership development programmes and establish peer-learning schemes. The creation of instructional leadership positions within schools, with clear responsibility for individual and school-w'ide teachers' professional development (e.g. classroom observation, mentoring, appraisals), is critical to improve the pedagogical knowledge and practice of in-service teachers.