Acoustic waves, especially high-intensity ultrasound and shock waves, are used for medical imaging and, increasingly, in manipulation of cells, tissue, and urinary calculi. They are used to treat kidney stone disease, plantar fasciitis, and bone nonunion, and are being investigated as a technique to ablate cancer tumors and mediate drug delivery. In many applications, acoustic waves interact with bubbles whose presence can either mediate the desired mechanical stresses and strains, or lead to collateral damage. Professor Colonius' interdisciplinary research group, uses theory and large-scale numerical simulations to study the dynamics and interaction of ultrasound and shock waves with inhomogeneous materials and bubbles, and to predict and optimize the local stresses and strains generated by insonification. They work with other engineers, scientists, and medical professionals to translate the fundamental mechanics into improvements in the design and clinical application of shockwave lithotripters.