Orchestra is a complete solution for Business Process Orchestration. It is based on the BPEL (Business Process Execution Language) standard defined by the Oasis consortium. It proposes an execution engine but also a designer, an administration console and a monitoring tool. The entire solution is completely open source under the LGPL license.
Orchestra provides the possibility to be plugged to ESBs. In particular Orchestra is proposed as the BPEL engine of the Petals JBI compliant ESB.