The author's group is active in research on a wide variety of solid-liquid separation and dewatering methods. Processes examined include coagulation/flocculation, sedimentation, consolidation, drainage, filtration, compression/expression, and desaturation. A number of mechanical and electrical techniques have been used. These have been applied to a few well-defined systems such as clays, and to a wide variety of real suspensions from different industry sectors, from small laboratory to large demonstration scale. The experience of a range of techniques allied widi knowledge of the characteristics and behaviour of suspensions is helping to bridge the gap between scientific understanding and practical application. The present paper, based on both published and unpublished CSIRO work with an emphasis on fine and ultrafine coal and coal tailings, summarises the position. The analysis includes: • conceptual evaluation of the applicability and limitations of established dewatering techniques, • considering better ways of using these techniques, • assessing the potential for combining force fields (how many, what type, what sequence) to provide improved dewatering technologies.