Purpose: This paper reviews the literature on patient-based assessments of implant therapy. Materials and Methods: A search of the literature produced 22 papers describing 19 studies. Results: Only 3 of the 19 studies were randomized controlled trials. Consequently, most have design flaws that threaten their internal validity. In addition, the measurement of patient-based outcomes was generally poor, further weakening the evidence provided by the reserach conducted tod ate. The randomized trials indicate that implants improve chewing ability and satisfaction with dentures but have not demonstrated effects with respect to the quality of life. Conclusion: Further research is needed using randomized controlled trial designs. Outcome measures need to be more carefully selected so as to reflect patients' concerns.