For hundreds of years the Maasai have moved their herds of cattle and goats across thousands of miles in Kenya and Tanzania. Today they face new challenges. Their traditional way of life is threatened, lands are overgrazed and wildlife is in danger. Maasai tribes are meeting these obstacles head-on - adapting their lives and agricultural practices while keeping their vibrant, close-knit culture alive. Award-winning author-photographer Jan Reynolds presents a striking glimpse of these dynamic people.