INTRODUCTION

National extension systems, comprising the public, private and nonprofit sectors, have played an important role in the last quarter century in transferring knowledge to raise agricultural productivity and promote rural development in many countries. This was facilitated by over 800,000 extension workers worldwide, with about 80 per cent of the world's extension services publicly funded and delivered by civil servants (Feder, Willet and Zijp 2001). International and local donors have also provided critical support to public extension systems worldwide. Between 1981 and 2004, the World Bank, for example, provided about $3 billion in direct support for extension. In relation to this role amid current developments, it is opportune to ask two important questions namely: (i) Can many of the national extension systems plagued with declining effectiveness overcome their problems, rise up to the demands of the occasion, and make their mark on agriculture and rural development? (ii) How can they be reoriented and/or restructured to maximize impact?

Historically, government policy has emphasized the public sector delivery of extension services to farmers, but the significant budgetary requirements and the weak performance of many public agencies over the last decades have become major government concerns. M any public extension systems have been widely criticised for being inefficient, ineffective, poorly linked to agricultural research systems, lacking clear objectives and motivation, not accountable to clients, and lacking relevant technologies. A nd such poor public sector performance has been attributed to a number of factors among which are: the weak political commitment and support to government extension agencies, thus adversely affecting implementation and funding; the allocation of resources, which is not aligned with local needs; the weak links between public expenditures and outcomes, exacerbated by weak monitoring and evaluation systems and the difficulty of measuring impact; the weak linkages between extension and knowledge generation agencies; and the frequent diversion of extension staff time to other duties (Umali- Deininger 1997; Purcell and A nderson 1997; Kydd et al. 2001; R ivera, Qamar and van Crowder 2001; Alex et al. 2002; Swanson and Samy 2004; Anderson and Feder 2005). These problems, in turn, have redirected attention to how to improve effectiveness, including reassessing the public and private sector roles in national extension systems.