Purpose of Review: Chronic rhinosinusitis (CRS) is a heterogenous disease process affecting a significant proportion of the population and impacting quality of life and productivity. Historically, CRS has been classified broadly into CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). Increased understanding regarding unique presentations of CRS subsets and their underlying inflammatory profiles has led to a new system for classifying CRS phenotypes. Recent Findings: Consideration of CRS phenotypes has traditionally been a key factor in determining treatment paradigms. Under a new phenotype classification system, physical findings will continue to drive treatment decisions, but with more precision. Summary: Recent rapidly accumulated knowledge indicates that the broad categorization of CRSwNP or CRSsNP is no longer clinically useful. Reorganization of CRS phenotypes and their underlying endotypes will lead to more targeted and efficacious therapy.