With warm vocals and an innovative approach to the fiddle, Lena Willemark has risen to the upper echelon of the Swedish music scene. Her solo recordings and collaborations with multi-instrumentalist Ale Möller and bands Frifot and Nordan Project have helped to bring the traditional music of her homeland up to contemporary standards. While she's been praised her for her "fine sensitivity and strength," The Planet noted that her "extraordinary, powerful voice can snap a listener's neck hairs to attention." A native of Evertsberg, a small village in Dalarna, Sweden, Willemark was first exposed to jazz and improvisational music in the late '70s. Her debut solo album, Nar Som Grast Det Vajar, released in 1989, received a Swedish Grammy and a German Music Critics prize. That same year she made her debut appearance with the Elise Einarsdotter Ensemble on Secrets of Living; she also appeared on their 1993 set Senses. Since 1990, Willemark has worked with Möller, a flute, octave mandolin, shawn, accordion, trumpet, bouzouki, hammered dulcimer, lute, percussion, and folk harp player from southern Switzerland. They joined with upright bass player Per Gudmundson to form Frifot, a group devoted to improvising on traditional Swedish tunes. Willemark and Möller formed a second band, Nordan, which specialized in reinterpretations of medieval ballads, in 1994. Willemark has increasingly drawn attention to her songwriting. In 1998, she debuted her composition "Windogur," written with composer Karin Rehnqvist as part of the Ladies' Next series commissioned by the City of Stockholm in its role as Cultural Capital of Europe 1998. The tune, which she performed with Bobo Stenson, Palle Danielsson, Lisbeth Diers, Staffan Larsson, Mikael Marin, and Mats Olofsson, was sung mostly in the regional language of Älvdalen. Additionally, Frifot released a self-titled album in 1999.

At the turn of the century, Windogur was recorded in a studio and appeared on Sweden's Amigo label. In 2001, she appeared on the Elise Einarsdotter Ensemble's album Summer Night.

Frifot released Sluring in 2003, which was nominated for a Swedish Grammis award. That same year, Willemark collaborated with Norwegian vocalist Kirsten Bråten Berg and percussionist Marilyn Mazur on the album Stemmenes Skygge; it was eventually released by Norway's Heilo label in 2005. She became a member of the Royal Swedish Academy of Music and performed often on its stage, as well as in Northern Europe as part of various traditional and classical groups.

A solo album, Älvdalens Elektriska, was released in 2006, followed by a Frifot disc entitled Fly T in 2007. Over the next several years, Willemark lent her instrumental and arranging skills to numerous recordings of her region's classical music from the 20th century; she was a member of the Country Eastern Band as well, which released a double-disc of regional holiday recordings in 2011. In 2013, she collaborated with Mats Oberg and Jonas Knutsson for Alla Drömmars Sång. This was followed a year later by The Nordan Suite ?with Möller and the Västerås Sinfonietta. Also in 2014 she recorded Years in a group with Anders Jormin, Markku Ounaskari, and Kari Heinilä.

Willemark made her first appearance on ECM in over a decade with 2015's Trees of Light, a series of contemporary compositions and improvisations in collaboration with Jormin and Japanese koto player Karin Nakagawa. ~ Craig Harris & Thom Jurek, Rovi