Some of the Funk Brothers he worked with include: Earl Van Dyke, Johnny Griffith, Robert White, Eddie Willis, Joe Messina, Dennis Coffey, Wah Wah Watson, James Jamerson, Bob Babbitt, Eddie Watkins, Richard "Pistol" Allen, Uriel Jones, Andrew Smith, Jack Ashford, Valerie Simpson, Eddie "Bongo" Brown, Benny Benjamin, Cornelius Grant, Joe Hunter, Richard "Popcorn" Wylie, Marcus Belgrave, Teddy Buckner and Stevie Wonder.
A graduate of Cass Technical High School in Detroit, Michigan, where he studied classical and jazz trombone, Paul was introduced to Berry Gordy at Motown by a friend who had already been working there.
He arranged hit recordings such as: "My Girl" and "Papa Was a Rollin' Stone" by The Temptations, "I Heard It Through the Grapevine" by Marvin Gaye, "If I Were Your Woman" by Gladys Knight & the Pips, "Reach Out and Touch (Somebody's Hand)[1] written by Ashford and Simpson and "Ain't No Mountain High Enough" as performed by Diana Ross (among other 1970s hits by the singer), and "The Tears of a Clown" by Smokey Robinson & The Miracles.
Artists that Riser has arranged for outside of Motown include: Luther Vandross, Phil Collins, The Carpenters, Carly Simon, The Doobie Brothers, Tom Jones, Quincy Jones, Natalie Cole, Aretha Franklin, Roberta Flack, Michael McDonald, Johnny Mathis, Mary J. Blige, and Patti LaBelle.
Riser arranged and conducted the strings on "I Believe I Can Fly," the 1996 Grammy award-winning song written, produced and performed by R&B singer R. Kelly.