In industrial liquid-liquid mass-transfer equipment, many a times the dispersed phases involved are highly viscous. The viscosity of dispersed drops influences the rate processes, especially their breakage rate. A new stochastic model for predicting the breakage frequency of viscous drops in a turbulent dispersion applying the random behavior of the turbulent fluctuations, has been proposed. It has been assumed that the correlation time of turbulent fluctuations across the viscous drops is so small compared to the time scale of drop deformation, that the turbulent fluctuation can be considered as a white-noise process. (c) 2006 Elsevier Ltd. All rights reserved.