Nasal delivery devices

A method of delivering substance to a nasal airway of a subject,

• comprising the steps of:
• fitting a nosepiece to a nasal cavity of a subject;
• the subject exhaling into a mouthpiece;
• providing a delivery device which comprises:
• a delivery unit, which comprises an actuation part which is manually displaceable to actuate the delivery unit to deliver substance from the nosepiece;
• and a valve assembly which is fluidly connected to the nosepiece and the mouthpiece, wherein the valve assembly comprises a body element and a valve element which is movably disposed to the body element between closed and open configurations by manual displacement of the actuation part of the delivery unit;
• and
• manually displacing the actuation part of the delivery unit to move the valve element of the valve assembly relative to the body element of the valve assembly between closed and open configurations and provide an air flow through the nosepiece simultaneously with delivery of substance.