A Web-based system for management of patients with symptoms of upper respiratory tract infection (URI) or sinusitis was developed and implemented for a primary care practice. Researchers conducted a retrospective analysis of the clinical records of 241 patients who accessed the Web-based protocol for these symptoms. A total of 137 patients (57%) fulfilled the criteria for management of their symptoms by registered nurses who followed established treatment guidelines; 51 patients were diagnosed as having URI symptoms and 86 with symptoms of acute sinusitis. For 84% of the patients with URI symptoms, no antibiotics were prescribed. First-line antibiotics were prescribed for 80% of the patients with sinusitis. The outcomes were no different from those of patients who had been treated with the same guidelines using a telephone protocol. Web-based protocolized care proved efficient, and exhibits outcomes similar to those derived from telephone-based treatment.