All frames needed example w 1492 (page 2) First (page 2) w 50 (page 0) First (page 0) w 15400 (page 30) First (page 30) w 15300 (page 30) w 180 (page 0) r 2200 (page 4) First (page 4) w 1292 (page 2) Construct a list in order of when pages are first used, ie: 2, 0, 30, 4 Use the last item, ie. remove frame containing page 4