Abstract The purpose of this study was to explore the development and course of social phobia by analysing qualitatively all the textual material obtained about the persons with treatment-resistant social phobia who, during the years 1995-2000, underwent a surgical procedure called endoscopic sympathetic block (ESB) to alleviate their phobic symptoms. In the other part of this study, the effect of this surgical procedure on social phobia was assessed quantitatively. The qualitative part of the study was based on the phenomenologic-existential philosophy and the principles of grounded theory. The qualitative analysis revealed four kinds of parenthood in the families of socially phobic persons: a violent, alcoholic type, a dominant type with high demands, a negligent type and a good enough type. A "vicious circle of social phobia" was formulated as a substantial category. The quantitative part of the study was an open, prospective follow-up study, where 169 patients operated on for social phobia during the years 1995–2000 were followed up for 5 years, and the changes in their symptoms were estimated using a modified version of Davidson's brief social phobia scale and the Liebowitz quality of life scale. The quantitative and qualitative parts of the study were linked together by investigating each person's family background with a semi-structured interview. According to variation analysis of the results, all symptoms of social phobia seemed to be alleviated highly significantly by ESB, and the results remained similar throughout the follow-up. Reflex sweating of the trunk was the only significant side effect. Overall satisfaction with the operation was estimated to be 3.5 on a five-point scale, representing the description "some help of the operation". Thus, ESB can be regarded as an additional treatment method for social phobia if traditional treatment with medication and psychotherapy has not provided any help for the patient.