Congenital neutropenia syndromes comprise a heterogeneous group of inherited disorders. Hereditary conditions associated with low neutrophil counts are persistent and need to be differentiated from neutropenia secondary to autoimmune processes or other pathologic conditions, such as myelodysplasia or leukemia. Clinically, congenital neutropenia is characterized by recurrent bacterial infections. Recently, several novel genetic defects were described in patients with congenital neutropenia, shedding light on the pathophysiology of these rare diseases.