Companies can benefit from diversifying internationally. This paper analyzes the internationalization efforts of six major European wireless telecommunications service providers: Telefonica, Deutsche Telekom, France Telecom, Vodafone, Telenor and TeliaSonera. Although all six companies have invested heavily in foreign markets, their internationalization paths have not been the same, resulting in foreign market portfolios with different characteristics. Utilizing a proportionate customer weighting scheme based on the number of subscribers controlled by a company in each market, the paper examines how the companies compared in 2007 versus 2002 in their extent and scope of internationalization and in the attractiveness of their foreign market portfolios with respect to some key growth, profitability, and risk market characteristics.