Beatrice Amblard, owner of the San Francisco atelier April in Paris, is obsessed with leather—but not as much as her customers are. The 38-year-old French designer, who perfected her technique during 14 years with Hermès, is known mostly for her handbags. But she also custom-makes pieces, from furniture to collar-stay covers, in skins like stingray, alligator, and ostrich. Amblard hand-dyes her leather to match the piping on a jacket or the green of someone's eyes. She's even done the interior of a Mercedes SL600 in beige calf. From $150 for a watchband to $10,000 for an alligator bag. At 55 Clement St.; 415-750-9910; www.aprilinparis.us.