The proficiency in new product development activities may be the key to the conversion of a market-oriented culture into superior organizational performance through better new product performance. To examine this conjecture our study tests hypotheses on the mediating effects of the proficiency in new product development activities and new product performance on the relationship between market orientation and organizational performance. The results from a sample of 126 manufacturing firms present evidence for the mediating roles of the proficiency in commercialization activities and new product performance. These mediating roles are consistent for three moderator variables: technological turbulence, market turbulence and innovation strategy. Together our findings provide a better understanding of how a market-oriented culture leads to superior organizational performance.