Goods and services ought to cater to human wants, needs, and tendencies. And they should cater to human diversity: the wide range of people, with each person having a range of roles. How? Design firm IDEO (centre-piece of Kelley’s The Art of Innovation and Kelley & Littman’s Ten Faces of Innovation) has a free tool kit and field guide.

IDEO HCD Tool Kit (PDF)

IDEO HCD Field Guide (PDF)

Overview and printed versions