Quality of life is widely discussed today as an important outcome variable in health care. The scientific interest focussing during most of the 20th century on illness enlarges its scope and includes well-being as an important goal and concept. Hence, quality of life (QoL) as a measure of well-being was included in many studies, but mostly determined by the purpose of the study and the external investigators. In order to weigh subjective needs and desires adequately, the Schedule for Evaluation of Individual Quality of Life (SEIQoL) was developed. This analysis is obtained from parameters chosen by the explored subject or patient himself. With the help of structured questions, the relevant dimensions of well-being for a given person are identified and put into context to the actually experienced situation. This method allows the sensitive detection of changes over time, and as a consequence of changes in life circumstances. It goes beyond the simple determination of health status and rather reflects the current state of the person as a whole.