The development of generalized sensitization during acute pain conditions plays an important potential role for the transition to and development of chronic pain. Such a phenomenon complicates adequate pain management and challenges current therapeutic modalities. This doctoral thesis aims to investigate the application of quantitative sensory testing in a clinical setting, mainly postoperative pain and chronic pain states. The pathophysiology, extent, and intensity of generalized sensitization, and in particular its relation to clinically relevant patient experiences, i.e. spontaneous pain and pain evoked by daily activities, are still a matter of debate and intensive research. The current thesis has taken on the difficult task of applying standardized quantitative sensory testing to clinical medicine to explore the extent and magnitude of sensory perturbation in a number of important conditions. The thesis is a very impressive and pioneering collection of important pieces of research providing a strong assertion on how pain can be diagnosed and profiled. It comprises an important contribution to the progress of the field and the impact of the studies will pave the way for new explorative studies for the benefit of patients suffering from chronic pain. Going from a purely descriptive way of thinking, the thesis has developed, in an ambience of changing concepts in pain medicine at large, a shift towards a mechanism-based way of thinking. This is the only way to make a step forward in pain medicine both when it comes to understanding the complex pictures presented by pain patients, and to provide clever answers to the complex therapeutic needs of these patients. The scientific work described in this thesis is original, and the findings contribute to new and better understanding of the pain syndromes investigated. This work also provides important information for planning future research. I have known and collaborated with Oliver since the early 1990s, and he is a true pioneer within the research to apply QST in the clinical setting. Therefore, I was extremely honoured when he chose to submit and defend his doctor of science thesis at the Center for Sensory- Motor Interaction, Aalborg University, and I am very much looking forward to our future collaboration and interaction in many years to come.