The category OI has objects the finite totally ordered sets and morphisms the order-preserving injections. There is a shift functor on the category of OI-modules. I will discuss what we know about an OI-module under iterated shifts and how it can be used to find an explicit bound for the Castelnuovo-Mumford regularity of the OI-module in terms of its generating degree and presentation degree. (This is a joint work with Liping Li.) Speaker(s): Wee Liang Gan (UC-Riverside)