Three phenomena in suspension continuum mechanics are discussed in this short paper. The first concerns the development of gel and ultimately yield stress in a stagnant column of initially well-mixed suspension. The second concerns the steady state that is observed to arise in wall filtration from a confined flowing stream, and the conditions needed to have an interface of discontinuity in solids concentration. The last concerns the dewatering of a dense suspension close to its equilibrium compaction when placed in a long column deviated from the vertical. The need for a multi-phase approach is emphasised.