Summoning is a mystical ability to call forth objects/creatures/people and is one of the spells featured in Disney's The Sorcerer's Apprentice.
The user can transport a person, a creature or an object of choice to their side where the object/creature/person was summoned by means of either teleportation or dimensional travel. How this spell works is by creating a mystical connection between the conjuror and the summoned object/creature/person, in which the method to do so was not shown on-screen. Although, the method to create the said supernatural connection was implied to be giving the enchantments on the desired object/person/creature so the conjuror can summoned them whenever they wish.
Because this spell was used once on screen, the potential drawback of this spell was unknown, though given to how the spell works, the conjuror must create the perfect mystical connection on the desired summoned object/person/creature.