“Billy Baldwin had a tremendous influence on me,” Mica Ertegün says of the pioneering midcentury interior designer. Ertegün, who cofounded her New York firm, MAC II, with the late Chessy Rayner in 1967, traces the earliest incarnation of her simple, “though not minimalist,” style to Baldwin. She describes his work as “very clean-looking, not cluttered, with very straight lines,” lacking the fussiness of his era and instead being far more modern than anything else happening at the time. These days, when seeking inspiration for her own clean-lined and understated interiors, which she fills with a rigorously chosen assortment of art and antiques, the Romanian-born designer and her staff of 11 turn to myriad sources. Mica Ertegün 212-249-4466 Although she eschews trends, believing instead “that the basic taste never changes,” Ertegün does keep an eye on recent developments in the field. She often finds that new products, be they wall finishes or building materials, can shape her vision on...