Particles are characterized primarily by their size distribution, density, shape, and surface charge. Particle removal processes in drinking water treatment plants include sedimentation or flotation, granular media filtration, and (or) sometimes membrane filtration. The effectiveness of these processes, as well as their design and operation, is determined by the characteristics of the particles in the influent to each process. The processes are linked, so that the results of one impact the results of another. Also, the treatment goals can vary from plant to plant, so that the desired results at the end of the plant might dictate the choice of earlier processes. These interactions are explored in this paper. Includes 4 references, figures.