Duo is an acoustic album by Richard Marx and Vertical Horizon vocalist Matt Scannell.^[1] The disc was released on May 12, 2008, exclusively through RichardMarx.com,^[2] and was later made available for sale at their concerts together as well. Marx and Scannell exhibit both of their acclaimed works. Marx remade a version of "Always On Your Mind," for his 2008 album Sundown.^[1] The disc is predominantly done on acoustic guitar aside from the track "Give You Back" performed on piano.

1. "Always On Your Mind" (Marx/Scannell) - 3:57

   new song

2. "Sunshine" (Scannell) - 3:40

   from the Vertical Horizon album Go

3. "Endless Summer Nights" (Marx) - 4:29

   from the Richard Marx album Richard Marx

4. "We Are" (Scannell) - 4:25

   from the Vertical Horizon album Everything You Want

5. "Hazard" (Marx) - 4:35

   from the Richard Marx album Rush Street

6. "Give You Back" (Scannell) - 4:25

   from the Vertical Horizon album Everything You Want

7. "Love Goes On" (Marx) - 3:46

   from the Richard Marx album My Own Best Enemy

8. "Echo" (Scannell) - 4:26

   from the Vertical Horizon album Go

9. "Your World" (Marx) - 5:07

   from the Richard Marx album Rush Street

10. "Everything You Want" (Scannell) - 4:31

    from the Vertical Horizon album Everything You Want

• Richard Marx – lead and background vocals, acoustic guitar, piano, producer, arranger
• Matt Scannell – lead and background vocals, acoustic guitar, producer, arranger
• Joel Numa – engineer
• Mat Prock – engineer