We review the current status of various programs developing phonon-mediated particle detectors for primary applications in particle and astrophysics. We begin with a brief summary and description of the general techniques employed by several of these groups. Experimental results on the detection of thermal phonons (e.g. using calorimeters) and athermal/ballistic phonons (e.g. using transition edge sensors or tunnel junctions) will be presented. Finally, we describe the design and operation of novel “hybrid” devices, and present results obtained with a cryogenic germanium hybrid detector which senses both phonons and ionization.