Multi-quantum well heterostructures (MQWHs) in the novel dilute nitride Ga(NAsP)/GaP material system have been grown pseudomorphically strained on GaP-substrate by metal organic vapour phase epitaxy (MOVPE). The group V-incorporation has been clarified as a function of growth temperature, chemical composition, gas phase V/V-ratios and macroscopic strain. An overall complex incorporation behaviour of the group V-atoms is observed. The precise adjustment of the V/V competition processes on the crystal surface allows, however, for a control of the solid composition of the Ga(NAsP)/GaP material system. (c) 2006 Published by Elsevier B.V.