Abstract A study has been made of the behavior of solid/liquid clusters undergoing simple shear in an immiscible liquid medium. Important criteria concerning the deformation and break-up of these clusters have been identified as they pertain to the efficiency of the separation of solid and dispersed liquid phases. Attention was concentrated on the effects of changing the volume fraction of solids within the cluster, the liquid/liquid interfacial tension and the wettability of the solid surface. An increasing volume fraction of solids was found to alter both the cluster strength and also the mode of rupture. Decreasing the liquid/liquid interfacial tension resulted in a lower overall cluster strength but increased the likelihood of emulsion formation, whilst the effects of three-phase contact on the break-up process was limited to clusters of high volume fraction.