The Arco floor lamp was designed in 1962 by the Castiglioni Brothers of Italy. The Arco, described as the perfect blend of form and function, is only one of their many triumps, as the brothers were renowned for their ingenuity and reformation of modern industrial design, even founding the ADI (Association for Industrial Design). While Achille Castiglioni was perhaps the most well known, brothers Pier and Livio were part of the dynamic design group, although Livio left them in 1952. 'This group have become one of the most witty, elegant and innovative partnerships in modern design. The brothers worked from the viewpoint that design must restructure an object's function, form and production process, and applied this maxim to every work that they produced. Castiglioni described this process with these words: "Start from scratch. Stick to common sense. Know your goals and means"'. Other Castiglioni treasures include the 'Mezzadro' (tractor stool) and the very industrial 'Toio' floor lamp.
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Where to Buy: New ones are available here and there as this lamp is still really popular - I know DWR has them. Its a better conversation piece though (and not to mention more eco), if its vintage; they pop up fairly frequently on eBay and Craigslist. I know AT found one for $250 once, but usually they are fairly pricey.