At about $15 a gram, saffron is the world's most expensive spice. Rumi Spice has a unique model of employing Afghan farmers who are growing it that aims to double or even triple their annual income. Cristina Hirschkorn/Courtesy of Rumi Spice hide caption

itoggle caption Cristina Hirschkorn/Courtesy of Rumi Spice

Luis Fernando Vasquez has been a coffee farmer in the central valley of Costa Rica his entire life. Dan Charles/NPR hide caption

itoggle caption Dan Charles/NPR

A coffee grower picks coffee fruits in a plantation near Montenegro in Quindio province, Colombia. Fair Trade USA wants to allow coffee from big estates like this one under its fair trade label. Jose Miguel Gomez/Reuters /Landov hide caption

itoggle caption Jose Miguel Gomez/Reuters /Landov