Are you using a Classic Scenario or Extended Classic? If Classic, then you must be creating Purchase Orders in the SAP R/3 system. There the output condition editor allows a lot of flexibility for controlling output.
However, if you are using the Extended Classic Scenario and creating purchasing documents in SRM, then the output control is fairly limited. The Condition Editor within the Set Output Actions and Output Format area in IMG provides some ability to control the output by Print, Fax, Email or XML. But this is very limited as compared to the SAP R/3 output controls.
This was first published in February 2007