In the present investigation we study the possibilities of using various types of sonic devices to provide controlled shear safely to disperse aggregates of biological cells at a rapid rate in a continuous flow system without damaging the sample cells. Such a device will be used in conjunction with automated cytological analysis. Controlled shearing in sonic systems can also be used to study the susceptibility of cells to mechanical shear and to achieve controlled release of organelles enzymes or biochemicals from cells. The shearing situation in several sonic systems is being investigated correlating acoustical spectral analysis, visual and photographic observations of oscillations in the systems as well as damage to biological test objects. The shearing situation is being investigated for jet-edge systems, arrays of vibrating wires and stable oscillating bubbles. Studies are also being conducted on efficient techniques to introduce biological cells into flow systems.