Choreographer Liz Lerman has a lot to celebrate. It was 20 years ago that she first started dancing with older people and other D.C. residents, trying “to make dance matter again.” Since then, the Liz Lerman Dance Exchange has become a rare phenomenon of substance over hype: Her intergenerational dance company is popular not because it’s a gimmick, but because it resonates as something exciting and genuine. In her one-night engagement at Lisner Auditorium, the company will revive Still Crossing, a piece Lerman created for the 1986 Statue of Liberty celebration. The piece—which will involve 50 dancers spilling off the stage into the aisles—is an exploration of identity and immigration in America. Lerman will also debut Nocturnes, a suite that gives new life and imagery to Willie Nelson standards like “Always on My Mind.” At 8 p.m. at George Washington University Lisner Auditorium, 730 21st St. NW. $15-23.50. (202) 833-9800. (Nora FitzGerald)