Short-Term Disability Insurance (SDI) follows the standard logic of other kinds of insurance
programs, such as health or life insurance, workers’ compensation, or unemployment insurance:
They pool individuals in order to spread the cost of a given individual’s experience with an
underlying risk among a large group, protecting each individual against the potentially
devastating cost of the covered event. SDI provides temporary, partial wage replacement to
employees who are unable to work because of non-work-related illness or injury.