Contrary to Jonathan Jones' comment in the Guardian, "The arts should take money from the devil himself", all cultural institutions make choices around which sponsors seem acceptable, according to changing attitudes in society: both tobacco and arms sponsorship were once seen as appropriate arts sponsors, but are no longer. In 2013 Norwegian music event ByLarm ended its deal with Statoil following intense public criticism, and in 2014 the Southbank Centre in London announced Shell would no longer sponsor its Classic International Series.A proponent of corporate sponsorship made the observation that "Businesses that simply try to art wash themselves in order to restore trust, will not always succeed." Artwash assesses oil sponsorship of the arts in its global formations, looking at the largest international oil companies Chevron, ExxonMobil, BP, Shell and Total, and the similarities with nationally-owned oil companies such as Rosneft and Statoil. BP and Shell sponsorship of galleries in London is of particular importance because the capital is a seat of power in the global oil economy, and as such cultural sponsorships in London are notably influential - what happens there sheds light on the broader issue.Reflecting on current discussion of the role and function of twenty-first century art museums, Artwash considers how the association with Big Oil might impede gallery staff in their endeavours. Misleading narratives around corporate sponsorship in the context of cuts in government spending on the arts blur the issue and the strategies of oil company PR executives to maintain brand and public image via these art museums reveal the primary purpose of corporate philanthropy. Galleries' curating and learning departments core activity is at stake, and the methods used by artists to challenge sponsors and the ethics of the art museum invoke the possibility of how cultural institutions might change.