Role and reference grammar (RRG) is a model of grammar developed by William A. Foley and Robert Van Valin, Jr. in the 1980s, which incorporates many of the points of view of current functional grammar theories. Role and reference grammar (RRG) is a model of grammar developed by William A. Foley and Robert Van Valin, Jr. in the 1980s, which incorporates many of the points of view of current functional grammar theories.