This collection of articles by leading Soviet Scientists reflects the latest investigations dealing with turbulence transitions, the emergence of stochasticity, and the appearance of coherent structures in hydrodynamic-type systems and the theory of strong turbulence. Possible applications of these new approaches to hydrodynamics, plasma physics, astrophysics, the theory of chemical reactions, and biophysics are discussed. Intended for specialists in nonlinear, turbulent and stochastic phenomena in physics.