[3][4] Koellner was raised in Brooklyn, and attended college at the University of Central Florida (UCF).
[2] She earned a Bachelor of Science degree in Business Management from UCF in 1977, and an MBA from Stetson University in 1980.
[5][6] After earning her bachelor's degree in 1977, Koellner began work at McDonnell Douglas as a contract analyst.
[7] She spent 19 years at McDonnell Douglas, with an end position of vice president of Internal Audit.
[19] In 2012, she was named executive chairman at the International Lease Finance Corporation (ILFC), a subsidiary of AIG.