The philanthropic instincts of rich Americans have long been a fruitful source of funding for good works around the world. The Rockefeller and Ford foundations are two leading institutions that have taken wealth generated by industrialists and used it to promote the public good not only in the US but also in other countries.

Now a new generation of the fabulously wealthy is putting its riches to good use. A new wave of philanthropy is emerging from the US west coast, where many information technology businesses are based. Most notably Bill Gates, chairman of Microsoft, is encouraging the treatment of Aids and malaria through a foundation he set up with Melinda, his wife. The Gates Foundation is spending and achieving more than many governments.