Ultrasonography is a versatile imaging modality that offers many ad- vantages over radiography, computed tomography, and magnetic resonance imag- ing. on Earth, the use of ultrasound has become standard in many areas of medi- cine including diagnosis of medical and surgical diseases, management of obstetric and gynecologic conditions, assessment of critically ill patients, and procedural guidance. Advances in telecommunications have enabled remotely-guided ultraso- nography for both geographically isolated populations and astronauts aboard the International Space Station. while ultrasound has traditionally been used in space- fight to study anatomical and physiological adaptations to microgravity and evalu- ate countermeasures, recent years have seen a growth of applications adapted from terrestrial techniques. Terrestrial, remote, and space applications for ultrasound are reviewed in this paper.