Designer Jennifer Weiss knows that artfully updating a pearl of mid-century design means discerning when to respect what's there and when to forge into the next century. Her thesis at Harvard's Graduate school of Design was on reworking modernist architecture, nicely situating her to refresh and add on to a boxy, L-shaped San Francisco bungalow from 1951 by influential Bay Area architect William Wurster. Her clients, Rebecca Handler, a fund-raising consultant, and her husband, David Andrade, a finance professional, had lived with their two daughters for about a decade in the 1,700-square-foot home before considering alterations. Though the need for a new kitchen was pressing-the oven hadn't worked in a year-Handler and Andrade worried that changing the space would mean losing original details, like the signature vertical-board redwood walls and the small, humanistic scale that Wurster favored. They need not have feared, however, because Weiss's careful interventions maximized what they already had-stellar views and a charming courtyard-while adding a new foyer, some additional square footage, a new wall of glass, and updated fixtures. Fittingly enough, Weiss's work is entirely in keeping with one ofWurster's great declarations: "Architecture is for life and pleasure ... and for people."