From condoms to toilets, why good design is essential for improving global health

A few years ago in a rural part of East Africa, one of our foundation's grantees was having an unexpected problem: its treadle pumps were selling very well in some places yet very poorly in others. Treadle pumps help farmers irrigate small plots of land and turn a subsistent yield into a surplus they can sell.

Our grantee started tracking who was and who was not buying the pump — and soon learned that sales were slow because of how the pumps operated. Farmers had to stand on the pump and pedal, a movement that required a lot of hip swaying, similar to riding a bicycle. That presented a problem in communities where cultural norms considered women's hips swaying to be inappropriate. As long as the pump operated that way, most women farmers simply weren't going to buy it, no matter how useful or profitable it could be. Once the grantee realized the problem, the pump was redesigned, and adoption rates shot up.