Apparatus for producing liquid droplets (for example an aerosol) is described. The apparatus comprises a vibratory element (106) arranged, in use of the apparatus, to vibrate an aperture plate (102) having at least one aperture therein. Also provided is a sealing element (202), which is arranged to provide a liquid tight seal over at least a portion of the vibratory element (106). The sealing element (202) comprises a closed cell foam material. In some embodiments, sealing element (202) may be molded over other elements of the apparatus, including the vibratory element (106).
