The Government of Ghana in 1989 instituted a performance monitoring and evaluation system (PMES) in the public enterprise sector as part of a national effort to improve the performance of that segment of the economy. Among other things, the PMES was designed to provide information to make informed judgment about the performance of these enterprises. The analysis takes the position that 20 years after its implementation, the PMES has not realized its full potential of providing useful information based on a systematic evaluation to guide policymaking and program implementation. The paper examines why so much attention is paid to monitoring to the detriment of evaluation and suggests corrective measures to help agencies achieve their potential. The lessons learned in this case study have implications for evaluation in other countries in Africa.