It is important to evaluate opportunity crude oils not only for cost savings but also for potential impacts on desalting, corrosion, environmental discharges, fouling, catalyst poisoning, and product degradation. Once problem areas have been identified, mitigation strategies should be developed and implemented to make the processing of the crude oil as profitable and trouble free as possible. There can be considerable batch to batch variation in some quality parameters so continued monitoring is required to minimize the potential for upsets. Examples will be given to illustrate monitoring and mitigation strategies.