Nasal polyposis is a chronic disease of the upper airways which adversely affects the quality of life of patients. Its pathophysiology is still unclear. Recently, several studies have shown different inflammatory pathways which relate to both innate and adaptive immune responses. Moreover, different phenotypes may exist in different ethnic groups of patients. This article will review recent data regarding the type of inflammation, cytokine profiles, involvement of macrophages and dendritic cells, and the impact of various organisms (especially Staphylococcus aureus and its superantigens) and their association with lower airway disease (especially asthma).