When a single-phase fluid splits, passes through identical paths in parallel, and then recombines, the flow distributes itself uniformly among the multiple paths. However, when multi-phase suspensions travel through identical parallel paths, the flow distribution can be significantly nonuniform. Although the uniform distribution is a solution of the governing equations, this solution may be an unstable steady-state solution between two or more stable solutions, or one of an array of possible steady-state solutions. This multiplicity has arisen in practice for multiple vertical channels within fluidized beds, for cyclones in parallel, and for distributed feed suspension flows. Simple theories are employed to explain the principles involved for two cyclones and for a pair of risers in parallel.