International scientists have come together to create a book on mechanosensitivity in cells and tissues. Mechanosensitivity, i.e. the specific response to mechanical stimulation, is common to a wide variety of cells in many different organisms ranging from bacteria to mammals. Mechanical stress can modulate physiological processes at the molecular, cellular, and systemic level. The primary target for mechanical stimulation is the plasma membrane of the cell, which can respond to variable physical stress with changes of the open probability of mechanosensitive ion channels. Thus, acting on ion channels in the plasma membrane, mechanical stress can elicit a multitude of biochemical processes inside a cell, both transient and long-lasting. This may ultimately influence the function of tissues and organs in health and disease. Several stretch-induced signaling cascades have been described with multiple levels of crosstalk between the different pathways. Increased sensitivity of the cells to mechanical stress is found under various pathological conditions. A detailed study of the underlying mechanisms may therefore help to identify novel therapeutic targets for a future clinical use.