An acoustic sensing apparatus (12) and method is for acoustically surveying the chest area of a subject, and in particular the rib cage. The apparatus includes an arrangement (16) of one or more sound sensors (18) and a controller (24), wherein the arrangement is configured to be placed on the chest of the subject in use, and to detect acoustic signals received from inside the chest. Based on the signal intensities picked up at a plurality of different locations across the chest, the different locations are each classified as being positioned either above a rib of the subject, or above an intercostal space of the subject. In a set of embodiments, the sound sensors are configured to sense sounds generated inside the body (e.g. heart and/or lung sounds, or vocal sounds). In a further set of embodiments, a sound generator may be provided for generating sound signals for transmission into the chest.
