Owing to information constraints in ambulatory care, concerned parties experience difficulties in understanding the German public healthcare system and recent healthcare reforms. The aims of this paper are to: 1) analyse information asymmetries between patients, physicians and the statutory health insurance; 2) evaluate patients' preferences (n = 1,315) with regard to reimbursement of out-of-pocket payments, which might overcome the market related information deficits; 3) assess whether the mechanism in which patients pay up front and get reimbursed may improve transparency and help publicly insured patients become more involved in their health and the healthcare system. Key results indicate that cost transparency would increase and individual responsibility would become more relevant.