For Diane Reyes, winning a client comes down to establishing trust.

In one instance last year, Reyes was trying to secure a contract with Kuwait's national oil company. During a sales call in Kuwait, she had given the potential client her home telephone and cell phone numbers, pledging 24/7 access. The businessman put her to the test, calling her on a Sunday after she returned to the United States. But perhaps most telling was a chance meeting between the two outside of Kuwait, at Dubai International Airport in the United Arab Emirates. In the bustle of the terminal, Reyes received a tap on the shoulder. The executive was in regular attire, rather than a thawb, a white robe worn by men in Persian Gulf States. "Do you recognize me?" he asked. She did, and the moment was one of many that helped establish the trust needed to win over another big client for Citi's Global Transaction Services, the arm of the bank that focuses on servicing treasury departments.

For Reyes, it also shows visiting with prospects trumps reaching them by telephone. "You have to call on them physically in person," she says. "Phone calls don't work as well as personal relationships."

To be sure, Reyes has positioned her group's focus on customers. She spearheaded an aggressive client-calling program for herself and direct reports, and since she took the reins of the Power, Energy, Chemicals, Metals and Mining group July 2008, she alone made 100 visits in a year.

Reyes has particularly targeted national oil companies of late. One key win was a deal with Petróleo Brasileiro in Brazil, second only in size to Reyes' deal with the Department of Defense in 2007.

"We have been focusing on this segment," Reyes says. "During a time of difficulty, we wanted to place extra attention on it and make sure we improve the results."

Reyes has also worked to shore up customer satisfaction. To increase global presence, she moved successful bankers to other regions such as the Middle East and Asia. To speed troubleshooting with clients, an executive in GTS was designated as a main contact within the bank's operations. Global conference calls were started, held every two weeks to discuss issues and strategize. Reyes also instituted a customer online training portal to help treasury departments navigate product sets and the intricacies of transactions.

"When you get satisfied customers, they tend to give you more volume in the future," Reyes says. "It becomes less of a bidding process and more of a natural evolution."

That was the case with PayPal, a Citi client. Reyes has shown patience with rollouts of PayPal's products overseas, willing to wait out delays and add advice when needed. "She has been extremely genuine and dedicated," says Jim Magats, director of global core payments in emerging markets and Asia-Pacific at PayPal. "Diane has invested in the relationship with PayPal, even in times when it didn't have a great short-term payout for Citibank."

Reyes is also a huge supporter of women in the workplace, serving as co-chair of The Women's Council, a group of 150 women at GTS committed to career advancement and leadership opportunities. With the group facing budget cuts, Reyes commissioned a survey to show how highly the women value training programs. Reyes also presented senior management hard numbers that show how the council's initiatives added to profits.

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