Great new feature of CRM 2013 is the ability to trigger a workflow synchronously, meaning I update a field, it triggers a workflow, that updates a field on the form in real time with no refreshing? Say goodbye to some plugins!
To make a workflow real time, click the actions menu and select real time option:
Once you have enabled this then you have a few more settings to work with to define how the workflow is triggered.
So depending on how the workflow is triggered will determine whether you can start the workflow process before the record has been created or after if trigger on create, otherwise if trigger any on change then again before or after and likewise on delete.
Another important point is how you execute the workflow. You now have the option to execute as the owner of the workflow thus the owner may have greater security permissions or run as the owner of the record that may have limited rights. Things to think about when designing workflows.
Like any workflow consider the impact of real time on performance and likely trigger ratio. In addition think about the impact that it may have on imports, we found real time workflows severely impacted the time to import records as real time workflows were triggered regardless of resource availability