Massimo Vignelli and Vignelli Associates
Massimo Vignelli formed design firm Vignelli Associates in 1971, with his wife Lella. The firm is responsible for some truly iconic work: the New York Subway transportation graphics and signage, the Knoll and Benetton corporate identity systems. Vignelli is an exponent of the grid system pioneered by Josef Muller-Brockmann; his work is clean and legible, but always beautiful.
Vignelli's book 'The Vignelli Canon' discusses his methods and experiences, and is available here as a free e-book.

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There's an interview with Massimo Vignelli over at Thirty Conversations On Design.
By Mark B @ 17:56
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Bob Noorda, the modernist designer responsible for the New York City subway signage while at Vignelli Associates, died January 11 at the age of 82. Click here for an NY Times article on Noorda's life and work.
By Mark Bell @ 12:13
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