Neutrophils are among the first immune cells to respond following infection or injury; this makes the possession of proficient pathogenkilling mechanisms essential. Phagocytosis, the process of detecting and engulfing particles into an organelle called the phagosome, is key to the ability of neutrophils to kill pathogens. In neutrophils, phagocytosis is a highly specialized and efficient event. Thus, neutrophils are the archetypal "professional" phagocyte, although monocytes, macrophages, eosinophils, and dendritic cells also display phagocytic ability to a somewhat lesser extent. 1 As well as killing ingested pathogens, innate immune phagocytes may present antigens to adaptive immune cells, highlighting the importance of phagocytosis for both arms of the immune system. 2 An intriguing neutrophil-dendritic cell hybrid phenotype has been identified in mice, exhibiting retained phagocytic and microbial-killing capacity as well as typical dendritic cell properties, such as antigen presentation. 3 The neutrophil phagosome is a distinctive organelle, formed from an invagination of the plasma membrane to completely enclose an engulfed particle. A host of complementary processes