The association between chronic rhinosinusitis (CRS) and allergy of the upper respiratory system has been discussed for many years,but much of this discussion has been anecdotal. Although epidemiologic evidence supports the increased prevalence of CRS among patients who have allergic rhinitis, and treatment of upper airway inflammation and allergy has been shown to decrease morbidity in patients who have CRS, but pathophysiologic mechanisms linking the two disease states have not been well elucidated. This article examines data supporting the link between upper airway allergic disease and CRS. It proposes a frame work for the treatment of CRS, with consideration of managing the allergic inflammation commonly noted in this disease. Finally, it discusses avenues for potential future research in evaluating the comorbidities of allergic inflammation and CRS.