A nasal delivery device for delivering substance to a nasal cavity of a subject, the delivery device comprising: a body member (101 201) a carrier (109 209) which is supported by the body member (101 201) and carries a plurality of substance-containing containers (C B) a nosepiece unit (119 219) including a nosepiece (147 247) for fitting to a nasal cavity of the subject a mouthpiece unit (121 221) including a mouthpiece (167 249) through which the subject in use exhales and an actuating mechanism which is operative, in each operation, to open a plurality of the substance-containing containers (C B), and including a valve unit (169 251) for fluidly connecting the mouthpiece (167 249) to a respective one of the opened substance-containing containers (C B) in successive exhalation cycles.
