In Hathaway v. Gen. Mills, Inc., 711 S.W.2d 227, 229, 29 Tex. Sup. Ct. J. 333 (Tex. 1986), the Court held that an employer may enforce changes to an at-will employment contract if the employer unequivocally provides notice of a definite change and the employee accepts the change by continuing employment. Hathaway, 711 S.W.2d at 229. In Hathaway, the Court explained the employee must have knowledge of the employer's proposed modification to an at-will employment policy to constitute effective notice; that is, the employee must "know the nature of the changes and the certainty of their imposition." Hathaway, 711 S.W.2d at 229. Requiring the employer to prove unequivocal notification of changes to the employment terms was based, in part, on fairness to the employee. See id. The requirement that an employee be aware that changes to the employment policy are certain to be imposed implies that there must be prior notice. It is unreasonable to conclude contemporaneous notice of a policy change is permissible under Hathaway. The Court held that the party asserting a change to an at-will employment contract "must prove two things: (1) notice of the change; and; (2) acceptance of the change." 711 S.W.2d at 229. The Court noted that "to prove notice, an employer asserting a modification must prove that he unequivocally notified the employee of definite changes in employment terms." Id.