The welfare effects of capital market integration are examined under a model of tax competition with two asymmetric countries. The asymmetry is expressed through the labour market: one country has a perfect labour market whereas the other country's labour market is unionized. Our results indicate that the welfare effects of capital market integration differ depending on whether governments are active or passive in attracting capital. In the absence of active governments, capital market integration benefits the country with a competitive labour market whereas it harms the unionized country. Capital market integration benefits both countries if governments are active and compete for mobile capital using taxes/subsidies.