The study examines the effects of Purchaser service management on Business development using Proma Paints Business in Lagos. Four research objectives were used, namely: to examine the impact of Purchaser service management (PSM) on the overall performance of an organization; to identify the specific areas of Business development that are most influenced by effective PSM; to understand the role of PSM in enhancing Purchaser satisfaction and loyalty, and how this translates into improved Business development; and to investigate the potential barriers to effective PSM implementation in business development. The target population consists of employees of Proma Paints Business in Lagos. A simple random sampling techniques was adopted for the study. Descriptive research design was used in the study. The study concluded that while PSM comes with its challenges, the benefits far outweigh the drawbacks. The study recommended that organizations should prioritize the implementation of PSM systems.