This paper analyzes the determinants of cross-border asset holdings on cross-country data and a Swedish data set. We focus our analysis on the effect of the euro not only for the determinants of bond holdings, but also of equity and banking assets. With the help of a simple theoretical model, we attempt to disentangle the different effects that the euro may have had on asset holdings for both euro zone countries and countries outside of the euro zone such as Sweden. We find evidence that the euro has implied 1) a unilateral financial liberalization which makes it cheaper for all countries to buy euro zone assets. For bonds and equity holdings, this would translate into a 14% and 17% decrease in transaction costs. Using Swedish data, we find...