William Leaf currently serves as the Head of the OSCE Centre in Ashgabat. Previously, he served as Politico-Military Officer at the OSCE Centre in Ashgabat. From 2008 to 2011, he held the position of Radio Programme Coordinator for the U.S. Central Command of the U.S. Department of Defense at the U.S. Embassy in Ashgabat, responsible for projects in Turkmenistan, Kyrgyzstan and Tajikistan (2008–2010). From 2011 to 2013, he served as Adviser on Export Control and Border Security at the U.S. Embassy in Ashgabat. In addition, he served as Head of the Department for Military-Political Affairs at the OSCE Centre in Kyrgyzstan.