W+K font here refers to the font used in the logo of Wieden+Kennedy, which is an independently owned American ad agency launched in 1982, best known for its work for Nike.
The font used for the company logo is probably Univers Light designed by Adrian Frutiger in 1957 for the Deberny & Peignot foundry in Paris. The typeface is a neo-grotesque, similar to its contemporary Helvetica. More details about it can be found here.
Download Univers Font
The Univers font identified above is not available for free, please follow the link above and purchase a font license to download and use the font. Meanwhile, you can take a look at our collection of fonts for cars, pop music and apparel as well as round-ups of new & fresh fonts around the web.