I have two customers that have the same workflow (Create file -transport file - wait for response - send response to internal team); however the implementation of each step is different for each customer. For example, one customer requires a flat file to be sent via SFTP, while the other customer requires an XML file to be sent via FTP. I'd like to create a sequential workflow, using Microsoft Workflow Foundation (WF) and reuse this workflow for multiple vendors. Each action's call to an external module can use the same interface, but a different concrete implementation. However, I'm unfamiliar with WF and I'm not sure how to implement this. Can someone point me to the proper way to use this pattern? Will it make a difference whether I choose WF 3.5 or WF 4.0? Thank you.