Liu and Idenburg first met in 2000 at SANAA in Japan while she was an intern and he was a senior associate working with Pritzker prize-winners Kazuyo Sejima and Ryue Nishizawa. In 2002, they met again in New York when Idenburg was working on the New Museum project in Lower Manhattan. They married in 2006 and founded SO-IL in 2008.
In 2010, the firm won the MoMA PS1 Young Architects Program with their playful, interactive installation Pole Dance. They went on to design a residence for designer Ivan Chermayeff in upstate New York, a wedding chapel in Nanjing, China, and the AIA New York award-winning Kukje Gallery in Seoul. They are well known for their inventive use of materials, exemplified in their office renovation for video production company Logan. This project divides the space into two identical, symmetrical rectilinear spaces. Each long room has a 65 foot continuous custom work table. Accommodating working groups of any size, the shared desks consolidate almost every operation of the company in one place: design, production, and meetings. Seamless, floor-to-ceiling translucent fabric walls separate the central work areas, visually breaking down the scale of the space, while maintaining a shared environment, and allowing natural light to penetrate.
In 2012 and 2013, SO – IL was commissioned to design the inaugural presence for the Frieze fair in New York City. Working with a prefabricated rental tent structure forced them to be inventive with a limited vocabulary. Pie-shaped tent section wedges bend the otherwise straight tent into a meandering, supple, shape. The winding form animates it on the unusual waterfront site, as well as establishing the temporary structure as an icon along the water. In Spring 2013, SO – IL won a competition to design the new Jan Shrem and Maria Manetti Shrem Museum of Art at the University of California, Davis. Plans for the museum include a 50,000 square foot permeable roof or "Grand Canopy" that blurs building edges, and creates a sensory landscape of a variety of activities and scales. The building is expected to be completed in 2016 and achieve LEED Platinum.