Abstract This paper presents an approach for computing the growth of Mode I, II and Mixed Mode I/II delaminations in carbon fibre reinforced polymer composites (CFRP) using a modified Hartman–Schijve equation. Unlike other equations it does not involve splitting the energy release rate into its various components. One advantage of this formulation is that the exponent of the associated power law appears to be independent of the mode as is the constant of proportionality. This formulation is shown to accurately compute the delamination growth rates associated with a range of Mode I, II and Mixed Mode I/II data available in the open literature. The potential for this approach to be used to overcome the no growth philosophy associated with current composite designs is also discussed.