A flexible piezoelectric transducer assembly for producing sonar signals for transmission underwater and for detecting reflected sonar signals. The assembly includes a generally flat, flexible casing formed with a plurality of compartments, each of which is for receiving a piezoelectric element. A plurality of piezoelectric elements are disposed in each of the compartments and are coupled by way of conductors to electronic circuitry which produces electrical signals for stressing the piezoelectric elements and which processes electrical signals produced by the piezoelectric element in response to reflected sonar signals. The piezoelectric elements are spaced apart in the casing to allow flexing and bending, while also maintaining high packing density. The piezoelectric elements are also selected to have low cross-coupling characteristics.