This article uses a responsive regulation perspective to explore relationships between standards organizations and state agencies in ostensibly private sector regulation of food quality and safety. First we will trace some of the history of the GLOBALG.A.P. private agri-food standard and then, using empirical case studies, highlight how this particular form of responsive regulation has played out in three distinct national contexts: Australia, the Philippines and Vietnam. In each case, the interplay between public and private sector regulation was pivotal in shaping the influence of private standards on social relations of production and on the subsequent evolution of regulation in both spheres. While there is an emphasis within GLOBALG.A.P. on benchmarking and harmonization, the interdependency between standards and national regulatory contexts means that neither the standards themselves nor the products that are certified against them are internationally uniform. Private–public sector interdependence creates competing imperatives at the international and national levels that are obscured by the language of harmonization but that nevertheless challenge the legitimacy and effectiveness of standards as a particular governance strategy.