This special issue of the International Social Security Review, prepared under the stewardship of guest editor Professor Bernard H. Casey, selectively addresses the key issue of the reform of social security programmes. As a central concern of many social security policy-makers and administrators, the process of reform can be long, complex and difficult. This being so, and in the search for solutions, aspirant reformers may choose to look abroad for evidence of “good practice”. This search for “good practice”, as a means to inform national debates, firmly underlines the importance of identifying and analysing the potential impact of “policy learning”; hence, the chosen focus of this set of papers. In many countries, the role of social security administrations in the reform process is restricted to, and only commences at, the policy implementation stage. It is the International Social Security Association's (ISSA) belief that in the pursuit of successful, inclusive and sustainable reform, there is greater scope for making earlier and more systematic use of the existing and often untapped “know how” of social security administrations. For the ISSA, the reform of social security programmes should address two key objectives: reform should be concerned with improving the efficiency and effectiveness of the internal workings of programme administrations and all their operational procedures; and it should also be concerned with better tailoring benefits and services to the expressed coverage requirements of populations. On this basis, social security reform should help better ensure the sustainability, legitimacy and relevance of social security institutions and, no less important, the benefits and services they deliver. These are key aspects of what the ISSA refers to as Dynamic Social Security. As part of its triennial work plan (2008-2010), the ISSA has highlighted the challenges presented by the need for social security reform. By investigating to what degree and in which ways policy learning may help to address these challenges, the findings presented in this special issue will contribute in a significant manner to the debate that will take place during the World Social Security Forum to be held in Cape Town, South Africa, from 29 November to 4 December 2010. The clear expectation is for the ISSA to provide all its stakeholders with a more complete understanding of the positive potential of social security administrations to proactively engage with, and bring their unique expertise to, social security reform processes.