Rework is an insidious problem in the construction industry. According to the Construction Industry Institute (CII) Source Document 29, the cost of rework is 12.4% of the total project cost. However, these costs are just the tip of the iceberg, because they do not represent schedule delays, litigation cost, and other intangible costs of poor quality. Therefore, the complete cost of rework is estimated to be much greater than 12.4%. To effectively reduce the cost of rework, it is necessary to not only study the causes of rework, but also to study the effectiveness of activities designed to reduce rework. This research studied the relationships between rework activities and prevention and appraisal activities on four construction projects. This research addressed two questions: 1) What is the effect of prevention and appraisal activities on the reduction of rework, and 2) What is the effect of prevention activities occurring in the design phase on rework due to design errors in the construction phase? Based on the project data collect by the Quality Performance Management System (QPMS), this research concluded there was a slight relationship between increasing prevention and appraisal activities and the reduction of rework. There was a direct relationship between the increase of prevention activities in design and the reduction of rework due to design errors in the construction phase. The relationships were stronger for both questions at the project level than at the discipline level. At the project level, the aggregation of all the disciplines appears to negate the biases created within the specific disciplines. This research helps to provide real-world data to emphasize the importance of prevention activity in the design phase of a construction project. / Master of Science