Wireless networks have been evolved to heterogeneous overlay structure, in which various wireless technologies provide partial or full coverage of the service area. Another evolution direction is multi-service wireless networks. In multi-service networks, traffic of various QoS classes is serviced concurrently. In this paper, we propose a scalable and flexible network selection scheme for multi-service heterogeneous wireless networks. In the proposed scheme, the profiles are generated for users or cells to represent their characteristics in three categories, which are traffic status, mobility and QoS. The best cell is determined for each user via profile matching. The proposed scheme can be tailored to utilize the information available from the underlying wireless technologies. Via extensive simulations, it is shown that the proposed scheme handles the interplay between multi-service traffic classes more effectively than existing schemes. We discuss how the proposed scheme can be applied to the 3GPP LTE networks.