Voluntary carbon offsetting grows fast but is criticized and under-regulated. OFFCORR produces in-depth understanding on how citizens, organisations and experts make sense of offsetting, how it is practiced, how it is connected to other climate actions, and what kinds of regulation and governance are needed. OFFCORR studies offsetting as part of sustainability transformations, from grass-root level to market actors and legislation, using social psychology, political science and law. Together we will design, collect, and analyse interviews and surveys. The results provide a holistic picture of various levels of arguments and views regarding offsetting. OFFCORR will develop both novel scientific understanding and regulatory and market recommendations for policy makers and market actors for a more holistic, legitimate and effective voluntary carbon offsetting. OFFCORR will engage a variety of stakeholders to make future-oriented strategies to manage tensions regarding offsetting.