Previous research has associated the development of social phobia with parental rearing practices, learning influences such as conditioning, vicarious transmission and verbal acquisition, and the individual's own response to social situations. The present study aimed to further investigate these possible antecedents of social phobia. A Learning History Questionnaire (LHQ) was completed by patients with social phobia (n=55), patients with posttraumatic stress disorder (PTSD; n=30), and non-patient controls (n=30). The LHQ focused on events that occurred before the age of 14 (the median age of onset for social phobia). The results indicated the importance of parental rearing practices such as not actively encouraging participation in social situations and emotional coldness. Difficulties with peer group were highlighted as important contributors to conditioning experiences. Individual response factors, especially post-event rumination, are potentially associated with the development of social phobia. Four of the 12 significant variables were unique to the social phobia group when the results from the PTSD group were taken into account. Further research is required to clarify the extent to which the environmental factors assessed in this study specifically contribute to the development of social phobia or to the development of anxiety more generally.