In Dendemille town, in a House, up and right from the Pokemon Center (next to some stairs), is the Move Deleter and the Move Reminder. The Move Deleter is to the left side of the house after entering, and the reminder is in the right side of the house.
Just like the previous Pokemon games, the reminder will not remind your Pokemon for free, you need a Heart Scale, carried by Luvdiscs or found in Rock Smash rocks.
Either catch them and take the item from them (at a cost of 200 per Pokeball), or use item-stealing moves in battle such as Thief and Covet, and take them off your Pokemon after battle. Luvdiscs are found in bodies of water, while fishing with an old rod.