As banks and payment companies battle for position in the new world of
"It's less about tech and more about trust," Marrs, group president of global merchant and network services at Amex, told American Banker. "Our card members need to trust the agent and the merchants need to know the transaction will work."
GMNS generated $4.9 billion in pretax segment income in 2025. Marrs has helped expand Amex's global merchant network to more than 170 million locations and the number of acceptance locations 500% since 2017.
Marrs reports to Amex CEO Steve Squeri and is the most senior female business leader with P&L responsibility at Amex, and is a member of the executive committee — contributing strategies for growth, risk partnerships and international expansion.
Marrs, who leads a team with about 7,000 employees with 12 direct reports, helps lead Amex's adoption of AI and generative AI as part of her portfolio.
She also played a role in recent acquisitions, including Amex's March 2025 purchase of Center, a company that sells business software. And in late 2025, Marrs helped launch
Marrs' other responsibilities include partnerships, including Delta, Hilton, Microsoft and Coinbase. Gen Z and millennials represent 65% of new global account acquisitions, a key part of Amex's strategy to attract younger consumers.
Amex is using AI agents to automate parts or all of tasks such as credit underwriting, fraud detection, and personalized customer service. The firm recently launched the Graphite Business Cash card, part of a pipeline of AI-powered products.
Other AI uses include streamlining marketing campaigns and to get those campaigns out faster. And while Amex has used AI to manage credit, risk and fraud for more than a decade, it has expanded AI to include analysis of more data sources.
Marrs' additional duties include oversight of American Express' credit and fraud risk organization. Her team's models evaluate transactions to detect fraud, manage credit risk and enable seamless approvals.
To manage risk in agentic AI, Amex is relying on its closed loop model, which includes direct relationships with merchants and consumers, to help it monitor an entire transaction to battle fraud. "Most consumers are using AI today for research but most do not use AI to transact," Marrs said. "It's still early days."
As consumers start using AI to make purchases, Amex offers purchase protection to refund payments in the event of an error. "A mechanism like this will be critical to building trust in the system," Marrs said. "It's like the early days of online shopping when people wouldn't know it would work."
