Cross–training is the process of teaching employees how to operate equipment, support an application or provide a service. It is used for backup support and mentoring. If the primary support contact is on vacation, s/he has one or more backups to support the operation(s) while s/he is gone. Cross–training should occur regularly providing updates to any substantive changes in process, so they can provide effective support. As the training sessions become more detailed, the backups get a more gestalt perspective of the processes and techniques in each other's area of expertise. This process has the added benefit of transplanting research and development (R&D) efforts from one support system to another without other employees having to undergo the same R&D in the other project.