The Euston Manifestoən/ is a 2006 declaration of principles signed by a group of academics, journalists and activists based in the United Kingdom, named after the Euston Road in London where it had its meetings. The statement was a reaction to what the writers argued to be widespread violations of left-wing principles by others who were commonly associated with the Left. The manifesto states that "the reconfiguration of progressive opinion that we aim for involves drawing a line between forces on the Left that remain true to its authentic values, and currents that have lately shown themselves rather too flexible about these values".
These alleged violations mainly concerned Middle East issues, including the Iraq War, the Israeli–Palestinian conflict and the war on terror. Broadly speaking the group asserted that the Left was over-critical of the actions of Western governments, such as the military presence in Iraq, and correspondingly was overly supportive of forces opposing Western governments, such as the Iraqi insurgent forces. The document says "we must define ourselves against those for whom the entire progressive-democratic agenda has been subordinated to a blanket and simplistic 'anti-imperialism' and/or hostility to the current US administration."
The manifesto proposed a "fresh political alignment", which involves "making common cause with genuine democrats, whether socialist or not", in which the Left stands for democracy, freedom, equality, internationalism, the open-source movement and historical truth, while condemning all forms of tyranny, terrorism, anti-Americanism, racism and antisemitism, including any form of it that "conceal[s] prejudice against the Jewish people behind the formula of 'anti-Zionism'".
The signatories said they "reject fear of modernity, fear of freedom, irrationalism, the subordination of women", and
reaffirm the ideas that inspired the great rallying calls of the democratic revolutions of the eighteenth century: liberty, equality and solidarity; human rights; the pursuit of happiness ... But we are not zealots. For we embrace also the values of free enquiry, open dialogue and creative doubt, of care in judgement and a sense of the intractabilities of the world. We stand against all claims to a total — unquestionable or unquestioning — truth.
The Euston Manifesto was accused of supporting the 2003 invasion of Iraq, equating opposition to the state of Israel with antisemitism, and attempting to rally pro-imperialist sentiment among the Left.
The authors and their collaborators call themselves the "Euston Manifesto Group". There are about thirty members of the group, and a larger number of signatories, four of whom were most heavily involved in authoring the document: Norman Geras, Marxist scholar and professor emeritus at Manchester University; Damian Counsell; Alan Johnson, editor of Democratiya; and
Shalom Lappin. Other members included Nick Cohen of The Observer, who co-authored with Geras a report on the manifesto for the New Statesman; Marc Cooper of The Nation; Francis Wheen, a journalist and authority on Marx; and historian complete list) Signatories include figures such as Padreig Reidy, editor of Little Atoms; Neil Denny, Interview Editor of Little Atoms; Oliver Kamm, columnist at The Times; Paul Anderson, a former deputy editor at the New Statesman; Marc Cooper, contributing editor at The Nation, among many others. 
The manifesto began as a conversation between friends, a gathering of (mainly British) academics, journalists, and activists. At their first meeting in London they decided to write a "minimal manifesto", a short document summarising their core values. The original intention of its proposer was that the manifesto would provide a rallying point for a number of left-leaning blogs, to be collected by an aggregator, and the basis for a book collecting some of the best writing about related political questions. The group met more formally after the document's first drafting, at a branch of the O'Neill's Irish-themed pub chain on London's Euston Road—just across the road from the British Library—where the manifesto was named, and its content voted on.