Objective: To assess the test-retest reliability of two questionnaires for measuring activity limitations in patients with Complex Regional Pain Syndrome type 1 (CRPS I) of the lower extremity. Design: Patients filled out the Walking Stairs Questionnaire and the Questionnaire Rising and Sitting Down twice during a one-week period. Setting: Outpatient pain clinic of a university hospital. Patients: Twenty-one outpatients with CRPS I of the lower extremity. Results: The Walking Stairs Questionnaire and the Questionnaire Rising and Sitting Down were reliable in terms of test-retest reliability as expressed by Spearman's r (range 0.79-0.90 and 0.85-0.89 respectively) and the ICC (range 0.78-0.84 and 0.84-0.87 respectively). Conclusion: Both questionnaires form a reliable tool for measuring activity limitations of patients with CRPS I of a lower extremity.