Although chief complaints of nasal symptoms naturally evoke a differential diagnosis with primary sinonasal disorders at the top, there exist systemic conditions that not only cause sinonasal symptomatology but also first present in this manner. These conditions generally fall into the categories of granulomatous and autoimmune diseases, diseases of impaired mucociliary clearance, and immunodeficiency. These conditions can lead to sinonasal symptoms that mimic or even cause primary sinonasal conditions such as chronic rhinitis or chronic and recurrent rhinosinusitis. In these cases, a successful management plan requires diagnosis and treatment of the underlying systemic condition. A failure to recognize systemic conditions as the cause of sinonasal symptomatology may lead to delays in diagnosis and appropriate treatment, and unnecessary patient morbidity. In this expert lecture presentation we will present individual cases of patients with sinonasal manifestations of systemic conditions (in the above-described categories). Discussion amongst the expert speakers will also provide unique and complementary perspectives on diagnosis and treatment. Through discussion of cases, we will provide practical clinical insights by explaining key signs and symptoms that can be used in the primary evaluation of the sinonasal patient to prompt early identification of an underlying systemic condition. At the conclusion of each case presentation, we will 1) review the most recent epidemiology and associations between the illustrated systemic condition and its corresponding sinonasal manifestations and 2) summarize practical clinical points. At the conclusion of the presentation, we will incorporate insights provided by the speakers into an algorithm which attendees can implement in their own practices, for early identification of systemic conditions that may be the underlying cause of common sinonasal symptoms.