GPA fulfils its role as a national Representative Organisation (RO) for the grains industry in accordance with the Primary Industries and Energy Research Development Act 1989 (PIRD), and has key responsibilities under the Primary Industries (Excise) Levies Act 1999 and the Primary Industries (Customs Charges) Act 1999. 

GPA is supported by Grain Levy Payers in Australia and through direct grower members and state affiliates.