The particle-based mesoscale simulation technique called Multi-Particle-Collision Dynamics (MPCD) (also denoted as Stochastic Rotation Dynamics (SDR)) is introduced. The algorithm is outlined and applications to complex fluids are described. Results for the dynamics of a Gaussian polymer and a rodlike colloid are discussed. Moreover, the density dependence of the diffusion coefficient of a colloidal fluid is presented. Our investigations show that the MPCD algorithm accounts for hydrodynamic interactions. (c) 2005 Elsevier B.V. All rights reserved.