Bonsiepe saw “interface” as a new “approach to design” — the subtitle of his book. And in a 2003 interview, he said, “I developed a reinterpretation of design as the domain of the interface where the interaction between users and tools is structured. I consider this not a minor contribution to design theory”.

In explicating his “approach” — his framing of design as “interface”, Bonsiepe made several related “moves”:

• Claimed design as a ‘fourth way’, separate from art, science, and technology.
• Distinguished designing from engineering.
• Provided an alternative to frames which cast design as primarily about cosmetics, aesthetics, drawing, or form.
• Defined the need for theory in design practice.
• Connected design theory and design practice.
• Embraced the idea that language is a fundamental element of design practice.
• Linked the verbal and the visual in design.
• Provided a theoretical basis for a new design discourse.
• And perhaps even reformed the modernist ideal.Guy