Monitoring and evaluation (M&E) isan extremely complex, multidisciplinary and skill intensiveendeavor. Government-wide M&E is even more so because itrequires detailed knowledge across and within sectors, aswell as of interactions among planning, budgeting, andimplementation functions in the public sector. The situationis complicated even further when the machinery of governmentis decentralized, with powers and functions distributedacross three spheres of government. This paper outlines theprocess of implementing a government-wide monitoring andevaluation (GWM&E) system in South Africa. The firstsection sketches the context that created the impetus forestablishing such a system. This context is clearly shapingthe evolution of the system and influencing its longer-termsustainability. The second section outlines the variousstages of conceptualizing and implementing the GWM&Esystem, which is currently very much a 'work inprogress.' The third section reviews internationalexperiences for lessons learned, which may also be germaneto the South African context, noting similarities anddifferences in approach. Some of the critical implementationfactors relate to the role of political leadership andchampioning of M&E, incentives for promoting usage ofM&E findings, dealing with information and dataconstraints, capacity building, "ownership" of theM&E system by line ministries and other agencies, andmanaging the challenges of change. The fourth sectionexamines a range of challenges and difficulties encounteredin South Africa. The final section reflects on lessonsdistilled from the South African experience to date.