This paper explores the policy-making process in the 1990s in two countries, South Africa and Zambia, in relation to health care financing reforms. While much of the analysis of health reform programmes has looked at design issues, assuming that a technically sound design is the primary requirement of effective policy change, this paper explores the political and bureaucratic realities shaping the pattern of policy change and its impacts. Through a case study approach, it provides a picture of the policy environment and processes in the two countries, specifically considering the extent to which technical analysts and technical knowledge were able to shape policy change. The two countries' experiences indicate the strong influence of political factors and actors over which health care financing policies were implemented, and which not, as well as over the details of policy design. Moments of political transition in both countries provided political leaders, specifically Ministers of Health, with windows of opportunity in which to introduce new policies. However, these transitions, and the changes in administrative structures introduced with them, also created environments that constrained the processes of reform design and implementation and limited the equity and sustainability gains achieved by the policies. Technical analysts, working either inside or outside government, had varying and often limited influence. In part, this reflected the limits of their own capacity as well as weaknesses in the way they were used in policy development. In addition, the analysts were constrained by the fact that their preferred policies often received only weak political support. Focusing almost exclusively on designing policy reforms, these analysts gave little attention to generating adequate support for the policy options they proposed. Finally, the country experiences showed that front-line health workers, middle level managers and the public had important influences over policy implementation and its impacts. The limited attention given to communicating policy changes to, or consulting with, these actors only heightened the potential for reforms to result in unanticipated and unwanted impacts. The strength of the paper lies in its 'thick description' of the policy process in each country, an empirical case study approach to policy that is under-represented in the literature. While such an approach allows only a cautious drawing of general conclusions, it suggests a number of ways in which to strengthen the implementation of financing policies in each country.