Jeffrey Sachs is a superstar. His advice contributed to the mess in post-Communist Russia, but that did not hinder him in any way from dispensing advice elsewhere (I met him when came to Sri Lanka in 2002; after I told him what we had done or were doing on telecom, he moved on to dispense advice on other topics). His opinion matters much. He has described the mobile as the single most transformative technology for development. He expands on this statement in an interview on AllAfrica.