We investigate the determinants of short term wealth effects for both public acquiring and target shareholders following the announcement of UK acquisitions over the period 1990-2005. Regardless of their nationality, overall acquirers incur losses, with domestic acquirers underperforming cross-border acquirers in general. For the latter no differences in returns between regions are found once the differences in corporate governance regimes are controlled for.Instead it is firm characteristics and in particular firm leverage that largely explains acquirers returns. All targets gain significantly but the higher returns associated with international deals disappear once bid characteristics are controlled for.