Visited Tanzania's Northern Circuit national parks in May 2013. Nearly 25% of Tanzania's surface is dedicated to national parks and conservation areas. Some have world heritage status. The future of the world would look brighter if all countries were as nature-conscious as Tanzania - and if the despicable demand for, and illegal trade in, ivory, rhino horns, lion bones(powderized) etc. could be terminated. It is especially Far Eastern countries like China, Vietnam and Laos who nourish this market, because of vanity and superstitious beliefs that rhino horn is any better for virility than chewing your own finger nails.
See also my video Ngorongoro highlights.