New research suggests the government's strategy to tackle gang crime is based on false assumptions. Dr Judith Aldridge, of Manchester University, explains why.
Chris McGreal reports from Zimbabwe on how Robert Mugabe's henchmen are using a hospital ward to torture prisoners.
The island of São Tomé was told 10 years ago that it had vast offshore oil reserves. Xan Rice explains why it has yet to see a drop of oil, and why most Africans don't reap the benefits of such a windfall.
Media correspondent Owen Gibson explains why record companies and Hollywood studios may benefit from the global economic downturn.
And science correspondent James Randerson outlines the pitfalls of a planned mission to Mars.
