Monodisperse emulsions can be obtained by shearing a crude polydisperse one. The aim of this paper is to discover the required conditions for droplet fragmentation and resulting monodispersity, independently of the chemical nature of the system. We particularly examine (i) the role of the initial emulsion viscoelasticity and (ii) the nature of the applied shear. Taking into account these features, we show a large variety of monodisperse materials that are easily producible in reasonable quantity.