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Todd Zaki Warfel

Todd Zaki Warfel


Designer and maker of things in SF Bay—mostly digital. Known for that prototyping book, guerrilla research, mobile first. Adventurous foodie, father & more...

Todd is a senior UX designer at Inflection and was a founding partner at Messagefirst, where he focused on design-research for consumer and b2b products. A recognized leader in the design-research and usability fields, Todd speaks regularly at universities and industry conferences and contributes to industry publications. With more than 16 years of industry experience; degrees in English, creative writing, and cognitive psychology; and a background in product design, Todd has been fortunate enough to create more than 15 industry-first products.

Todd is a storyteller by nature and is rarely short on details. He is an active member in a number of industry communities and organizations, including the Information Architecture Institute, IxDA, and UPA.

He has done work with a variety of clients, including Albertsons, AT&T Wireless, Bankrate, Bank of America, Comcast, Cornell University, Dell, IntraLinks, Palm, Sallie Mae, Splenda, SBC, SUNY, and Tufts University.

Todd currently lives in the Bay Area and blogs at


Principles for Prototyping

8 principles

Todd Zaki Warfel