 The IKL collected data on waiting times and treatment of NSCLC patients treated in 2001 and 2004. These data will be used for this project. In addition, the MAASTRO lung database contains information of patients treated in 2006 and 2010. Additional information about the diagnostic procedure and radiation treatment preparation will be collected by reviewing the patient charts. For this study a data request has to be submitted to the IKL and access to MAASTRO patient data charts and EMD is needed. 