The University Medical Center Freiburg is the largest hospital to be certified by the (de) (KTQ, Cooperation for Quality and Transparency in Healthcare), the most widespread certification procedure at German hospitals. The aim of KTQ is to make a voluntary certification procedure available to hospitals and to promote continuous improvement and internal quality management.[10] The KTQ certification seal is valid for three years, after which a reevaluation must be performed. The University Medical Center was first certified in 2005 and recently recertified in 2008.[11]