The Technical Committee on Physical Acoustics (TCPA) of the Acoustical Society of America (ASA) includes scientists and engineers with an interest in the underlying physics of acoustical phenomenon. What unifies the members of TCPA is the approach to answering a particular question. The types of phenomena of interest to the physical acoustics community are fundamental acoustic wave propagation, including transmission, reflection, refraction, interference, diffraction, scattering, absorption, and dispersion of sound covering the entire frequency range from infrasound to ultrasound. There is also interest in the use of acoustics to study physical properties of matter, and to produce changes in these properties. TCPA currently has about 575 members with a primary interest in physical acoustics with 75–125 typically attending open TCPA meetings.