RSG's first subsidiary, ThinkRisk, began business in December 2009 to provide underwriting and claims management services for media, technology, advertising and network security.

[12][13][15] During his senior year, Ryan earned $8,000 selling personalized scrapbooks to dorm residents, an experience that "kindled his entrepreneurial spirit".

[14] After graduating from Northwestern University, Ryan immediately joined Penn Mutual's Chicago office as a life insurance agent.

This move transformed Pat Ryan & Associates into a nationwide business, and in 1971, with $25 million in annual sales, he took the firm public.

[12] The company continued to expand through organic growth and acquisitions, and in 1987, Ryan changed Combined's name to Aon Corporation.

At Ryan's retirement in 2008, Aon operated with more than 500 offices in 120 countries generating revenues in excess of $7 billion.

[29][30] The music and communications building, which opened in 2015, was named after the Ryans for their longtime support of the arts at Northwestern.

[34][35] In 2023, Krissie Harris, a candidate running for Evanston City Council received two $6,000 donations made by individuals connected to Pat Ryan.

Evanston's Community Association For Better Government suggested the donations gave the appearance of a "quid pro quo" agreement between Pat Ryan, who wants the Evanston City Council to approve plans to re-zone and Rebuild Northwestern's Ryan field, and Krissie Harris.

These include, among others: In 2004, Ryan hosted President George W. Bush during a political fundraising dinner at his home in Winnetka, Illinois.