Another form of OTJ training is job rotation. Also know as cross-training, job rotation involves moving an employee from one position to another at regular intervals in order to enable the employee to develop expertise in a variety of job. Although job rotation increases the variety tasks that an employee can perform, it does not increase the complexity of the employee's job at any one time. Job rotation allows an employee to enjoy more job variety and to gain a more complete sense of the organization's functions, as described in INSIG. It also enables an organization to assign employees effectively during vacation or overload period.