The objective of this study was to identify health related problems encountered during an annual mass gathering in Pakpattan, Pakistan, the anniversary of the death (urs) of Baba Farid, and to make recommendations for planning and prevention activities. A surveillance system was established to capture health related data for the event. A list of reportable diseases was developed. Data were collected pre-, during, and post-event by health care workers trained for the purpose. A total of 5918 people reported to the 15 health care facilities providing services during the event; 58% of consultations were because of communicable diseases, 21% of which were respiratory tract infections and 26% gastrointestinal illness. Injuries accounted for 31% of cases and noncommunicable diseases for 11%. Prevalence of reportable disease during the event showed sizeable increases. No major disease outbreak was observed.