Barreto started his coaching and managing career in 2003 when he managed Ghana’s team till 2004. He has managed over 11 teams in his career so far.
From Ghana he moved on to manage “Maritimo” football team and managed them for a year too. In the year 2005, for a few months he was asked to manage the “Al-Nassr FC” team. Later in 2005 he joined in as the assistant manager of “Dynamo Moscow” team.
In the following years talented Barreto coached “Naval 1 de Maio” and “AEL Limassol” from 2006-2007 and 2007-2008 respectively.
One of the turning points in Barreto’s career came when he officially registered as assistant coach of “Kuban Krasnodar” in 2009.
After this, he was asked to manage “Recreative Do Libolo” and “Al-Qadisiyah”, which he did two years each from 2009-2011 and 2011-2013 respectively. Then came the biggest milestone of his career when he was selected to take over as the head coach of the famous team “Ethopia” in 2014 and he did this job till April 2015.