Pity the payments executive who travels to countries where the merchants don´t take his network's cards. Every restaurant bill and hotel check-out brings the indignity of paying with another brand of card - and giving business to his competitors.

So for David Nelms, who has spent the last three years filling in Discover Financial Services´ acceptance gap in Japan, a trip there this week will include an unusual victory lap.

"For the first time in all the years I´ve been traveling over there, I´m going to check into my hotel with my Discover card," said Nelms, Discover´s chief executive, in an interview Thursday. "I´m looking forward to that."

Nelms is traveling to Japan this week to mark his network´s reciprocal acceptance agreement with the country´s largest network, JCB Co. Ltd. Under that agreement, signed in 2006, Discover will be "turning on" in Japan this month, he said.

The Diners Club International network, which Discover bought from Citigroup Inc. last year, is already accepted in Japan, as are Visa Inc., MasterCard Inc. and American Express Co.

Discover would not provide more details about Nelms´ trip or say which card brand he had previously used in Japan.

Nelms, who was interviewed after Discover reported its fiscal second-quarter results, said the trip also highlighted some of the gains made by Discover´s network business, which has struggled to compete in the United States.

For the quarter that ended May 31, Discover´s network volumes rose 11% from a year earlier, to $58.7 billion, bolstered largely by Diners Club and the Pulse debit business. Third-party Discover network volumes (from cards issued by other financial institutions) fell 16%, to $1.3 billion.

Nelms said he was "really pleased" with Discover´s payments business this quarter.

"We´re making some very good progress on that, and I know that kind of gets lost with all of the appropriate focus on credit quality, but we are continuing to invest," he said. "It´s full steam ahead on the network."