How to set up an workflow in SharePoint to only work when a specific field is changed and not everytime the item is edited?

Question

The issue is that everytime an item is edited/changed all the users who are set up to receive updates are notified. I need the workflow to run only when a specific field is changed disregarding the others. For example if my item contains these values (Customer Name; Acc#; Contact Person; Address;) - I need the workflow to work only when the Acc# is changed and only if it is changed, no metter how many times the other fields are changed.

Thanks,

Answer 1

You should create an event handler to run on your content type or library. You can then check the before and after properties of the fields you mention. Then use the event handler to initiate the workflow if required.

Answer 2

A quick way to do it is to have the workflow store the value each time the it starts, then tell it to wait until the field != the stored value. This may not work in all cases, but it could be enough for your purposes.