The First IEEE International Workshop on Scientific Workflows (SWF 2007) was launched at Salt Lake city, Utah, as part of the First IEEE World Congress on Services (SERVICES 2007), in conjunction with IEEE SCC/ICWS 2007, attracting around 20 attendants including 5 presenters and a dozen of submissions. SWF 2008 was held in Honolulu, Hawaii, in conjunction with IEEE SCC, with around 25 attendants including 9 presenters (3 of them were invited speakers) and a dozen of submissions. SWF 2009 was held in Los Angeles, CA, in conjunction with IEEE ICWS, with around 30 attendants including 20 presenters (10 for regular papers, and 10 for short papers). SWF 2009 also enjoyed the event of the launch of the first IEEE International Conference on Cloud Computing (CLOUD 2009). SWF 2010 was held in Miami, Florida, with around 25 attendants (9 papers), in conjunction with IEEE CLOUD/ICWS/SCC. SWF 2011 was held in Washington DC, in conjunction with 11 accepted papers, some of which explored cloud-related workflow issues.