The Wall Street Journal goes in depth with the architects of the new SFMoMA extension:

The challenge for the addition is to be both iconic and largely invisible to a neighborhood that didn’t want another tower, said Craig Dykers, principal of Oslo architecture firm Snøhetta, which is leading the design. “We are not interested in creating sculptural monuments. We are interested in creating social monuments,” said Mr. Dykers. “We were intrigued by the idea that this wasn’t an expansion, but a connection to those who live nearby.”

The complex will include 40,000 square feet of free public space and galleries that are largely visible at the street, which the architects hope will encourage people to congregate. Snøhetta’s design shifts the orientation of the city block inward by tapping an existing dead-end street in the middle of the block, called Natoma, for a major new entrance.

SFMoMA Thinks Big in Expansion (WSJ)