Phagocytosis is perhaps the key goal to which the activity of myeloid cells such as neutrophils and macrophages is directed. In vivo, neutrophils triggered to leave the blood stream, migrate through the extracellular matrix (ECM) and are guided to sources of microbes in order to kill them after phagocytosis. Methods for quantifying this event in vitro are therefore useful in the experimental assessment of agents and conditions that may modify the phagocytic ability of the phagocyte.