The Maasai Mara National Reserve has a unique concentration of wildlife because, unlike much of the Serengeti to the south, it has a year-round supply of water. It supports a huge resident population of herbivores and the predators that feed on them and attracts the Great Migration from August to October. But the Maasai Mara is not a national park; the land still belongs to the Maasai. Visitors pay an entry fee, so there is an incentive to maximize their numbers, with dire environmental consequences. Fortunately, there has been a recent growth of “conservancies,” areas of land contiguous to the reserve that the owners have elected to devote to wildlife tourism. Combined, they are already nearly as extensive as the Maasai Mara itself. Conservancies can channel profits into schools and clinics and enforce responsible rules about the number of visitors.