The Recording Academy has made a number of changes to its rules, most notably allowing samples to be used on songs nominated in all songwriting categories, including the all-genre song of the year.
Previously, samples - snippets of previously recorded material or songs incorporated into a new work - had been allowed only in the Grammy Awards' best rap song category.
The academy also reorganised the Gospel and contemporary Christian category, formalised the definition for the alternative music field and added a category for best American roots performance.
The addition means 83 awards will be given at the 2015 Grammys, bringing the American roots music field into step with other major categories.
The changes, announced on Thursday, were made at the academy's recent spring Board of Trustees meeting.
