Roaming, that is calls made on networks other than a subscriber's home network, could be worth US$50bn a year worldwide according to roaming specialists Roamware Inc. But, says Roamware CEO John Hoffman, GSM operators who are not tuned in to the potential of controlled roaming could be handing over lucrative roaming revenues to rival networks. "Mobile phone network operators that do not give roaming subscribers their full attention are potentially losing out," comments Hoffman. "And it's not about getting subscribers to spend more, it's about getting them to stick to the right partner networks, and to be able to use the same services when they roam that they use when at home. Roaming is not longer about the availability of service, it's about the capability of the services you can access when you roam." If roaming subscribers are properly served, says Hoffman, they will make more use of their phones and that means that home network operators will win more revenues from their partner networks. With the implementation of enabling technologies for data, roaming services have entered a new era. Providing transparent access may prove to be the difference between success and failure in terms of revenue generation.