Improper design, operation and maintenance of the steam jet air ejector (SJAE) system result in elevated condenser pressures with attendant loss in plant capacity. Conversely, problems associated with the condenser and circulating water system may be incorrectly attributed to the SJAE system. This paper provides an overview of SJAE systems for nuclear plants. It discusses sizing of venting equipment, examines the interface of the SJAE system with the condenser, explores performance issues encountered with the SJAE system and shows how to evaluate its performance. The Heat Exchange Institute Standards for Surface Condensers and Steam Jet Vacuum Systems are also discussed. The paper provides conclusions and recommendations for troubleshooting and monitoring the performance of the SJAE system and for ensuring optimum performance.