[2] Lewallen's first worked at Bykert Gallery in New York, where she met Michael Snow and Vito Acconci.
[3] After moving to Los Angeles, Lewallen worked for Cirrus Editions and Broxton Gallery (with Larry Gagosian).
[6][3] Lewallen also worked as associate director of Crown Point Press, a fine-art printer and publisher, in the 1980s and 90s.
[3] "State of Mind New California Art circa 1970", curated with Karen Moss in 2011, was a seminal contribution to the history of West Coast conceptualism.
[3] In addition to her work on conceptualism, Lewallen was known for her solo shows of single artists, including Theresa Hak Kyung Cha, Bruce Nauman, Joe Brainerd, Jay DeFeo, and Paul Kos.