After meeting the Swedish folk-jazz pioneer Bengt-Arne Wallin and trombonist Eje Thelin, Landgren was persuaded to move from his strictly classical studies to improvisation and to begin developing his own sound and approach to music.

[3] Skifs's band, Blue Swede, recorded a number one hit song in the U.S. pop charts with Hooked on a Feeling.

[1][4] In 1981, Thad Jones invited Landgren to join his big band, called Ball of Fire, as the lead trombonist.

By his own reckoning, he has contributed to at least 500 albums by such international groups and musicians as ABBA, The Crusaders, Eddie Harris, Bernard "Pretty" Purdie, Wyclef Jean, and Herbie Hancock.

The album Live in Stockholm was released that year and was the foundation for the collaboration with Siegfried Loch and his then nascent label ACT Music.