The paper describes an application based on Virtual and Augmented Reality technologies specifically developed to support maintenance operations of industrial products. Two scenarios have been proposed. In the first an operator learns how to perform a maintenance operation in a multimodal Virtual Reality environment that mixes a traditional instruction manual with the simulation, based on visual and haptic technologies, of the maintenance training task. In the second scenario, a skilled user operating in a multimodal Virtual Reality environment can remotely train another operator who sees the instructions about how the operations should be correctly performed, which are superimposed onto the real product. The paper presents the development o...