A nasal delivery device for and a method of delivering substance to a nasal airway of a subject, the delivery device comprising: a nosepiece for fitting to a nostril of a subject, the nosepiece including a nozzle through which substance is in use delivered to the nasal airway, and at least one cuff member which, when fitted in a nasal cavity of the subject, is such as to engage an inner wall of the nasal cavity of the subject and direct at least a distal end of the nozzle towards a site in the nasal airway of the subject and a delivery unit for delivering substance through the nozzle of the nosepiece.
