What Is Supplemental Executive Retirement Plan? 
A supplementae executive retirement plan or SERP is a form of non-qualified deferred compensation . Since the planned is non-qualified , the employer has the ability to select who participate in the plan -LRB- i.e. they can choose to offer such a plan only to a select number of employees and do not have to make the offer to everyone -RRB- . Traditionally the plans are set up as additional retirement benefits to an employee who is highly coveted by the employer . The plans are used as an incentive to keep certain key employees and disuade them from leaving the employer . The retirement benefits offered under the plan are only payable to the employee if he or she stays at the employer for a certain period of time , which can be a rather longer period of time . 