Primary ciliary dyskinesia is characterized by chronic upper and lower respiratory infections which are caused by the grossly impaired ciliary transport. Since the cilia and neutrophils both utilize microtubular system for their movement, it has been speculated that neutrophil motility such as chemotaxis might be impaired in patients with primary ciliary dyskinesia. Neutrophils were purified from whole blood from 16 patients with primary ciliary dyskinesia and from 15 healthy controls. Chemotactic responses of neutrophils to leukotriene B₄ (LTB₄), complement 5a (C5a), and formylmethion-ylleucylphenylalanine (fMLP) were examined using the under agarose method. The chemotactic differentials in response to LTB₄, C5a, and fMLP in neutrophils from the patient group were significantly lower than the corresponding values in neutrophils from the control group (p<0.05 for all comparisons). The difference in chemotactic index between the two groups was statistically significant for LTB₄ and fMLP (p<0.05 for both comparisons), but not for C5a (p=0.20). Neutrophils from patients with primary ciliary dyskinesia showed a decreased chemotactic response as compared with those from normal subjects. It is concluded that the increased frequency of respiratory tract infection in patients with primary ciliary dyskinesia is possibly due to the defective directional migration of neutrophils, as well as to the defective mucociliary clearance of the airways.