AbstractConstruction projects are significantly affected by uncertainty and variability. Traditional management uses result-oriented indicators to control project performance, which present limitations to detecting and preventing deviations. The Last Planner System (LPS) proposes an alternative focused on the systematic task of analyzing the intermediate scope, preparing work, and managing short-term plans through commitments. Although the benefits of LPS have been studied, most quantitative research has focused on work accomplishment metrics, such as the percent plan complete (PPC). This research studied the relevance of work preparation and the relationship between constraint management and project performance. The relationships among work preparation, short-term compliance, and project performance were addressed in five equal progress intervals throughout project execution to study the correlations between PPC, percent constraints removed (PCR), and the schedule performance index (SPI) in 69 construction projects. Also, the correlations between 10 LPS metrics and 3 outcome metrics at project completion were addressed. Then the projects were classified according to their schedule accomplishment outcome to assess differences in 11 LPS metrics. Statistically significant correlations were found among constraint management, short-term compliance, and schedule accomplishment; also, statistically significant differences in constraint management indicators between projects with high and low schedule performance were identified.