Jazz pianist Marcus Johnson takes his role as a performer -- and what audiences should expect from that performer -- very seriously.

If you go Marcus Johnson Project Where: Blues Alley Jazz Supper Club, 1073 Wisconsin Ave. NW When: 8 and 10 p.m. Sunday Info: $27.50; 202-337-4141; bluesalley.com

"I tell people all of the time that musicians are really in the therapy business," said the 38-year-old, who has been performing professionally since 1995. He will play two shows Sunday at Blues Alley.

"Our job is to make people's day better; to make the morning commute less painful, the drive home better, and then to do it all over again the next day," he said.

Added to that, he said, is the beauty of live performance that gives him the opportunity to directly engage with the people he hopes he is helping.

During the last 15 years, Johnson has released 11 solo jazz records, with his 12th CD, titled "This is How I Rock," due out at the end of July. While the majority of his work is original, the music on this latest release contains his favorite works by other artists, such as "Come Together" by the Beatles, Sly and the Family Stone's classic, "Thank You (For Letting Me Be Myself)" and "Mais Que Nada," the Sergio Mendes hit.

These, along with hits from his previous albums, such as "Poetically Justified," "In Person: Live at Blues Alley" and "In Concert for a Cause" will be included in the performance with his quintet tonight.

A native of Montgomery County, Johnson received both a law degree and an master's in business administration from Georgetown University before deciding to make his living at the piano. He put his advanced business degree to good use when he founded his record company, Three Keys Music, located in Silver Spring.

During the course of his career, Johnson has shared the stage with such luminaries as BB King, Peabo Bryson, Diana Krall, Chuck Mangione and Chaka Kahn and has made appearances at the Capital Jazz Fest, the Bermuda Jazz Fest and the Kennedy Center, to name a few.

About the intimacy of Blues Alley, Johnson said, half soberly, half jokingly: "I like the fact that right off the side of my keyboard are [people] that will let you know whether you're doing the right thing or not. Their eyes are closed and they're moving back and forth, and that's when you know you have someone."