This TechBrief presents the methodologies and procedures used by the research team in the analyses of the Long-Term Pavement Performance (LTPP) data to develop and implement pavement performance measures and to analyze treatment effectiveness. The LTPP study focused on using data from the various LTPP experiments to define pavement performance in a way that supports the selection of cost-effective pavement treatment strategy and to better estimate pavement treatment effectiveness and the role of pavement treatments in the pavement’s lifecycle. This TechBrief includes a description and examples of the dual pavement condition rating systems, LTPP data analyses results, and application of the analyses to datasets from three State transportation departments.