Ultrasound‐mediated diagnosis techniques have consistently attracted worldwide attention. Compared with other medical‐diagnosis methods, relatively distinguished features of ultrasound being readily accessible, swift, inexpensive, and safe make it routinely used for diverse purposes. With the development of ultrasound‐imaging devices, the recent advent of ultrasound contrast agents (UCAs) has expanded the sphere of ultrasound's influence to therapy. UCAs, which are generally gas‐filled and microsized bubbles, have been grafted onto multifunctional particles or molecules to selectively detect various diseases and effectively treat them. Additionally, nanosized bubbles as well as microsized bubbles have lately received a lot of attention since the phase‐transition behavior of the bubbles is observed under certain conditions. The focus here is an introduction to and the preparation of therapeutic and multimodal UCAs. Also, high‐intensity focused ultrasound (HIFU), among the ultrasound‐mediated techniques, which enables researchers and health‐care providers to overcome existing approaches, is described in depth. To close, the future and challenges of diagnosis and therapy with ultrasound are reviewed.