Systems thinking dominated the 2015 World Social Marketing conference with the premise that a more holistic approach takes into account all the issues at play for effective change. Augmenting the broadening social marketing literature, we contend that systems-thinking social marketing enhances the field’s conventional behavioural change with concepts of scale, causation, and iterative co-creating change processes for complex health and environmental problems. The results of our empirical Sea for Society study, a sustainable European marine ecosystem examination of what the barriers to change are and how they are interrelated, find systems-thinking social marketing offers the potential to strategically and critically reinforce, not replace, behavioural change campaigns. With systems-thinking social marketing, a coherent theory of change becomes a possibility. Orchestrating social change may become a reality.