The practice of evidence-based medicine (EBM) relies on the ability of veterinarians to evaluate clinical outcomes. Evaluation of clinical outcomes optimizes the patient care process by transforming what is learned about a population of patients and applying it to an individual patient. Veterinarians' ability to summarize and record relevant information from each pet encounter enables outcomes analysis, thereby transforming clinical data into medical knowledge. This article describes the multiple integrated processes required to evaluate outcomes and practice EBM. As a result of the aggregation and analysis of patient outcomes, knowledge is derived that has the potential to enhance clinical decision making and client communication.