Abstract Background Self-efficacy is related to outcome after anterior cruciate ligament (ACL) tears. The Knee Self Efficacy Scale (K-SES) available in Swedish and English, was developed to measure self-efficacy in present (K-SESpresent) and future (K-SESfuture) functioning. The objective of this study was to determine measurement properties of the K-SES in Dutch patients. Methods The K-SES was translated and structural validity, internal consistency, test-retest reliability, and measurement error were assessed in three patient samples: one group completed the questionnaire and additional measures pre-surgery (N = 200), and one group post-surgery (N = 58). The third group (post-surgery) completed the K-SES twice (N = 50). Results Exploratory factor analysis distinguished two underlying important factors: K-SESpresent and K-SESfuture. However, the distinction was not confirmed in Confirmatory Factor Analysis (CFA). Internal consistency for both subscales was excellent (Cronbach’s alpha > .80). Test-retest ...