Marian Harper's has been with the Astros organization since 1992. In March of 2008, she was named vice president of foundation development and currently oversees the expansion and day-to-day operations of the Astros in Action Foundation. The AIAF was established in 2000 during the Astros inaugural season at Minute Maid Park. The mission of the Astros in Action Foundation is to use the strength of the National Pastime to enhance the quality of life in the community through educational, health, and spiritual endeavors. Major fundraisers for the foundation include the Astros FanFest, Race for the Pennant - 5K Run/Walk, Pink in the Park luncheon and the Astros Alumni Celebrity Golf Classic. Marian also oversees the Grand Slam for Youth Baseball program with Minute Maid. She was named vice president of community development on July 22, 1999, after serving as the director of that department since November 1997. Under her guidance, the department assisted thousands of organizations annually through memorabilia and monetary donations, appearances, community awareness programs, player involvement, and the Astros mascot program. She was also responsible for all youth outreach initiatives, including educational programs and the youth fan club.

She joined the Astros in 1992 as promotions coordinator, overseeing purchasing, distribution and account services for in-game activities. Marian is a native of Pittsburg, Texas. She currently serves on the Board of the Northeast YMCA where she was named 2002 Volunteer of the Year, the Boys and Girls Clubs of Greater Houston, and The Ensemble Theatre. In November 2007, she was presented with the prestigious Toy Cannon Award by Astros icon Jimmy Wynn at the Texas Baseball Hall of Fame Dinner.