To prevent possible misunderstandings, Norman Geras and Mark Harvey, co-authors of ‘Marx’s economy and beyond‘, would like to put it clearly on record that their joint authorship does not entail agreement on all political and intellectual issues. There is agreement between us, naturally, about the content of the paper itself, though doubtless each of us might elaborate consequences, implications, nuances, etc, in his own way. But we did not agree – just for example – over the Iraq war and we do not agree about the Falklands/Malvinas. We also don’t see eye to eye on whether or not there is a universal human nature. More things could be added to this list, but a few examples should suffice to have made the point. We have produced our paper in common because we thought the arguments we shared regarding Marx’s political economy were substantial and important enough to put both of our names to them. For the rest, like other pairs of co-authors we agree about much but also disagree about plenty. It has been no obstacle in the way of working together as old friends. On the contrary, we have both enjoyed the collaborative effort involved, benefiting from one another’s different perspectives and intellectual resources.