Acoustic radiation force is widely used in biomedical studies and medical diagnostics. Among the promising areas of its application is concentration and stirring of particles and bubbles in ultrasonic resonators (e.g., [1]). In a number of cases, cylindrical resonators have a practical advantage vs. plane resonators (acoustic interferometers) due to the axial energy concentration [2], [3]. Theoretical analysis of particle dynamics in such resonators is often very complicated. This presentation outlines recent results in modeling of dynamics of micro-particles and microbubbles in cylindrical resonators. In particular, concentration and separation of “heavy” and “light” particles and near-resonant bubbles are discussed. The role of ultrasound nonlinearity in the considered effects is also discussed. [1]. A. Sarvazyan and L. Ostrovsky, J. Acoust. Soc. Am. 125, 3548–3554 (2009). [2]. A. Priev and A. Sarvazyan, J. Acoust. Soc. Am. 125, 2593 (2009). [3]. L. Ostrovsky, A. Priev, V. Ponomarev, and Y. Barenholz, P...