All patients presenting to the University of Washington Medical Center Sinus Clinic are screened for depression with the PHQ-9 as a standard of care in their evaluation, as well as a physical examination, nasal endoscopy, and CT scan. Those patients who meet diagnostic criteria for CRS and for major depression will then be treated with three weeks of maximal medical therapy. Maximal medical therapy includes three weeks of a second-line antibiotic (such as Augmentin, azithromycin, or a fluoroquinolone), possible oral steroids based on the presence of inflammation or polyps in the sinuses, and nasal saline irrigations. They will then follow up with Dr. Davis in one month from their initial evaluation. Those who still do not have significantly improved symptoms (considered medical failures) will be approached and introduced to the study by Dr. Davis's medical assistant and then referred to the research assistant for further discussion and offered enrollment and consent if entry criteria are met. Note that if patients present for their initial consultation and have received maximal medical therapy from the referring clinician within the past two months, then they will be approached for possible entry into the study at that time.