Rationale, aims and objectives Patients with anterior crucial ligament injury are faced with a choice between surgery or non-surgical treatment with intensive rehabilitation. Evidence shows that surgical treatment is not superior to non-surgical treatment. To offer patients a treatment meeting their individual values, lifestyle and conditions, patients must be involved in the decision-making. The aim of the study was to develop and evaluate a patient decision aid to support shared decision-making. Method Development of the patient decision aid was based on international criteria, current literature, and former patients’ experiences and suggestions on how to optimize the decision-making process. The patient decision aid was evaluated by the SDM-Q9 questionnaire and semi-structured interviews with patients and doctors. Results A patient decision aid for patients with and an anterior crucial ligament injury was developed. On a scale from 0-5, patients experienced a high degree of shared decision-making in their treatment decision both before (score 4.3) and after (score 4.3) implementation of the patient decision aid. No statically significant difference was found (p=0.72). From interviews, patients expressed that they found the patient decision aid very useful. Especially, reflection time was important for some patients. Doctors reported that the patient decision aid improved shared decision-making by supporting the dialogue clarifying patients’ values concerning issues important for treatment choices. Conclusion No statically significant difference in the SDM Q9 -score was found between patients’ perceptions of shared decision-making before and after implementation of a patient decision aid. However, patients experienced the decision aid as very useful when making treatment decisions, and doctors reported that it improved the dialogue clarifying patients’ values important for the treatment options. Keywords patient-centered care, evaluation, person-centered medicine