There are numerous weaknesses associated with industrial buyers collection and use of supplier performance evaluation SPE information a.k.a., past performance information. These weaknesses call into question the efficacy of SPEs. Neither the factors affecting SPE efficacy i.e., its antecedents nor the effects of SPE efficacy i.e., consequences on suppliers have been empirically explored. Despite the fallibility of SPE schemes, there are no known studies that explore the accuracy of SPEs, nor are there studies examining whether and how inaccurate SPEs affect suppliersspecifically, their performance. The purpose of this research, therefore, is to identify the factors affecting SPE efficacy, then to examine how SPE efficacy, in turn, affects supplier outcomes. This research will employ a mixed method of qualitative interviews and quantitative analysis of survey data collected from suppliers and from assessors of supplier performance.