Neutrophils, the most abundant circulating white blood cells in humans, have traditionally been considered a homogenous population of terminally differentiated cells with a well-defined and highly conserved function. Indeed, their short lifespan, their inability to proliferate, their limited capacity of de novo gene expression, and their limited ability to recirculate from the tissue to the blood-stream have for long sustained this idea. However, evidence accumulated over the past ten years has demonstrated a thus far underestimated functional versatility and phenotypic heterogeneity of the neutrophil population. Far beyond their antimicrobial functions, neutrophils are emerging as decision-shapers during chronic inflammation, tumor development, but also during homeostasis. Research performed at ExPat aims at understanding mechanisms of neutrophil production, maturation, and release from the bone marrow. In addition, we seek to understand how neutrophils contribute to chronic sterile inflammation including atherosclerosis and myocardial infarction and we design interference strategies to boycott such misdirected neutrophils responses.