Starting a Workflow at a Pre-Determined Future Date

Sep 10, 2009 at 6:29 PM

I would like a workflow to trigger 30 days prior to an end date (column) in my document library. Without resorting to some external reporting application, is it possible to have a workflow automatically start on a pre-determined future date? Currently SharePoint Designer offers 3 trigger options for workflows: new record, modified record, and manual trigger.