Multi-Tenant Workflow pattern

I am looking for some help on identifying the best design pattern for the following scenario.

I am building an approvals system that can be used by multiple approval companies. The basic process is:

Allocated to Team Assigned to Team Member Approved by Team Member Reviewed by QA Delivered back to Requestor

The workflow is essentially sequencial, but there may be some nuances on the number of reviews. New teams may want to skip a step or add an additional one. So what i want is the ability to have a "out-the-box" workflow but the ability to use inheritance to override the functionality. I have been going over it in my head for the last 48 hours and cannot figure it out but am sure i am missing some pretty elegant structure to make this work.