This excerpt taken from the GWW 10-Q filed Aug 2, 2006.
Exercise of SARs. SARs may be exercised at such times and subject to such conditions, including the performance of a minimum period of service, as the Committee shall impose. SARs which are granted in tandem with an Option may only be exercised upon the surrender of the right to exercise an equivalent number of Shares under the related Option and may be exercised only with respect to the Shares for which the related Option is then exercisable. Notwithstanding any other provision of the Plan, the Committee may impose conditions on the exercise of an SAR, including, without limitation, the right of the Committee to limit the time of exercise to specified periods.