A slider (41) for guiding the top of a sliding door (12) in a channel (42) comprises spaced cheeks (56) between which extends a rib (59) which engages one side of the channel, and flexible tongue (60) which flexes between the cheeks and is thereby biased into engagement with the other side of the channel. Another embodiment of door guide has a pair of wheels (113, 114) having enlarged rims at one end for engaging opposite walls of a door guiding channel. One of the wheels is inverted relative to the other. Thus, the rim of one wheel is at a higher elevation than the rim of the other wheel.