Two Concord women who spent their careers in vastly different worlds are hanging their paintings side by side for the first time. Susan Zellmann-Rohrer, a retired Silicon Valley software engineer, and Mary McWilliams, a former Islamic art curator, open "Oil and Water" Thursday at the Harvey Wheeler Community Center in West Concord, running through Sept. 10.

The pair met about five years ago at The Umbrella Arts Center, shortly after both had retired. Neither had seriously pursued painting before that. They kept signing up for classes together, became friends, and started going on what they call "art dates" — visiting museums or sketching side by side at Drumlin Farm.

"We couldn't have been really more different," Zellmann-Rohrer said. "Yet there was this sort of bond between us, which was art."

McWilliams, who spent her career as the Norma Jean Calderwood Curator of Islamic and Later Indian Art at the Harvard Art Museums, said starting something entirely new after decades of professional success demanded a kind of humility she hadn't expected. She'd wanted to paint for as long as she could remember, but work and family never left room for it. Both women are now in their early 70s — proof, in a way, that it's never too late to begin.

Their styles couldn't be more distinct. Zellmann-Rohrer chases atmosphere and mystery — one piece in the show is an abstract seascape inspired by Homer's "wine-dark sea" from "The Odyssey," while another is a still life of peaches built around a small orange glow she describes as the quiet "mystery" hiding inside an ordinary scene. McWilliams, by contrast, is drawn to shape, texture and physical presence, with works including a watercolor of Arches National Park and a portrait of a sleeping pig at Drumlin Farm, much of the white paper left deliberately untouched.

Both women hope the exhibition nudges other people to pick back up whatever they set aside during their careers or while raising families — a reminder that a late start is still a start.

The Harvey Wheeler Community Center is at 1276 Main Street in West Concord. Hours run Monday-Wednesday 8:30 a.m.-4:30 p.m., Thursday 8:30 a.m.-7 p.m., and Friday 8:30 a.m.-2 p.m. More information: 978-318-3020.