A Future in Rubbish

By AISHA LABI

Inspiration is sometimes found in the unlikeliest of places.

Take the case of Sammy Gitau, a onetime petty criminal and drug user who recently earned his master's degree from the University of Manchester, in England. One rainy day seven years ago in the slum of Mathare Valley, Kenya, Mr. Gitau spied atop a mound of refuse a brochure for Manchester's...