USC announced earlier today that it will offer four-year scholarships to football, men's basketball and women's basketball players, as opposed to the traditional one-year scholarships renewable at the end of each academic year.
The NCAA introduced the provision allowing the use of four-year scholarships in 2012, though most schools still choose to do it the old way and simply renew -- or chose not to renew -- each athlete's scholarship on a year-by-year basis.
"In taking this action, USC hopes to help lead the effort to refocus on student-athlete welfare on and off the field," USC athletic director Pat Haden said in a statement posted on the school's website.
Here's a sidebar story I wrote last summer about this topic as part of a bigger project for the Spokesman-Review, with some comments from folks at Washington State. Athletic director Bill Moos prefers it the old way in most instances.
Essentially, a four-year scholarship guarantees that as long as an athlete remains in good academic and behavioral standing, the school cannot terminate his or her scholarship for performance-related reasons (or, for example, due to injury).