VanWarmer was inspired to write "Just When I Needed You Most" by two events: his old car, that he loved and used for years, broke down on his way to work in Denver, Colorado, and he experienced a "devastating" breakup with a girlfriend.

[5] Released as a single in February 1979, VanWarmer's "Just When I Needed You Most" spent two weeks atop the US Billboard adult contemporary chart in May of that year[5] and in June 1979 reached its peak position of No.

4 on the Billboard Hot 100 chart, accruing an overall Top 40 tenure of 14 weeks and earning RIAA Gold record status.

Other artists who either recorded or performed the song in concert include country music singers Tim McGraw, Donna Fargo, Skeeter Davis, Rhonda Vincent and Conway Twitty, R&B vocalist Millie Jackson, the German disco musician Peter Griffin, British glam rock band Smokie, reggae artists Barbara Jones, and Eddie Lovette, Filipino singer Pops Fernandez, Bob Dylan, Paul Butterfield, Billy Joe Royal, and the Spanish group Mocedades.

[20] A Finnish rendering of "Just When I Needed You Most" entitled "Juuri Kun Tarvitsin Sua" was recorded by ELF (fi) for their 1979 album Tarantella-Joe.