In Tanzania, millions of people seek treatment for malaria through the private sector. But most cannot afford effective medicines. Now a pilot study is testing whether a drug subsidy scheme could help these patients, with some positive preliminary results.

On the eve of WHO's 60th anniversary, Udani Samarasekera asks health and development experts what they think some of the UN agency's greatest achievements and failures have been and how they believe the organisation needs to change to better address health globally.