Relatively little is known about the financial market impact of international monetary surprises arising on the same trading day. This paper estimates a suite of multi-security factor models, which captures international monetary surprise effects on UK and Euro Area government-bond markets over the period 1999–2014. In doing so, we shed light on the relative importance of coinciding, non-coinciding monetary surprises and non-monetary surprises across the yield curve. We find some support for the ‘enrich-thy-neighbour’ hypothesis of international monetary surprises, while our findings suggest that monetary policy cooperation during crises produces financial market effects that go above and beyond conventional policy.