Chronic rhinosinusitis (CRS) is defined as persistent symptomatic inflammation of the nasal and sinus mucosa. Although insights into the pathophysiology of CRS have largely expanded over the last 2 decades, the exact etiology is still unknown and is likely due to multiple host and environmental factors. Treatments are aimed at reducing mucosal inflammation, controlling infection, and restoring mucociliary clearance within the sinuses. The principal goal of this article is to outline a rational approach to the treatment of chronic sinus disease on the basis of currently available diagnostic and therapeutic techniques. Emphasis will be placed on the management, therapeutic response, and objective evaluation of therapeutic efficiency.