Europe's nine million business travellers are estimated to spend some US$ 750 million on telephone calls, in a market that is expected to grow at over five per cent a year for the next three years. In the UK, around £600 million is fed into public payphones every year. In the competitive battle between carriers for a share in these revenues, card services are becoming an important weapon. While margins on charge card services may be tight, the benefits to the carrier can be improved branding, and access to new customers in home markets and abroad. Meanwhile, smart card technology means that pre-paid telephone cards can be used to market a variety of goods and services, helping to spread costs and generate greater telephone usage.