Krista Donaldson uses design to fight jaundice, create prosthetic limbs, and solve some of the developing world’s most vexing problems. This is why we was selcted as the 2014 ALVA Award winner, a special prize presented by Behance in partnership with GE to recognize remarkable serial inventors.

In this 99U talk, she offers a peek into her team’s design process for getting complicated medical treatments to all corners of the world for a price anyone can afford. Chief among her advice? Talk to your customers. Then talk to them again. And use all that feedback to iterate and, when needed, drastically shift your design process. “We want closure on our projects…but people and society and technologies change. You want to be okay with the ambiguity.”