Dr. Tim Lubbers was awarded with an MLDS career development grant, with which he can perform a 4 year study with a budget of 250000 euro. This study will for a large part be performed in close collaboration with the VOC-team of our department. The title of the study is: The distinctive smell of colorectal anastomotic leakage: prevention, early detection and personalized treatment. Colorectal anastomotic leakage is a severe complication after colorectal surgery, but its origin is not yet understood. Changes in the exhaled volatile organic compounds (VOC) can possibly be used to diagnose and predict the occurence of colorectal anastomotic leakage, resulting in improved patient care. In Dutch: De karakteristieke geur van colorectale naadlekkage: preventie, vroege diagnostiek en individuele behandeling. Korte samenvatting: naadlekkage is een ernstige, veel voorkomende complicatie na darmchirurgie, waarvan de oorzaak anno nu nog niet bekend is. In dit onderzoek gebruik ik veranderingen in de samenstelling van uitademingslucht om het optreden van naadlekkage aan te tonen of te voorspellen en daardoor de medische behandeling van deze patiënten te optimaliseren.