XXVIII	Modification of Schedules
	1.	Allows negotiated withdrawals of concessions at the start of every three years.
	2.	Negotiated agreements may include compensatory adjustment, and the parties should "endeavor to maintain" at least the same overall level of trade liberalization.
	3(a)	Allows for withdrawal of concessions if negotiations fail, but then permits offsetting retaliation within six months.
	3(b)	A party with "a substantial interest" which is "not satisfied" with a negotiated agreement may retaliate within six months, following thirty days' notice.
	4.	"The CONTRACTING PARTIES may, at any time, in special circumstances, authorize...negotiations for modification or withdrawal of a concession" as long as the negotiations are consistent with this Article. "If agreement between the contracting parties primarily concerned is not reached within a period of sixty days" (or any longer prescribed time period), "the applicant contracting party may refer the matter to the CONTRACTING PARTIES." If no settlement is reached, unilateral withdrawal of concessions and retaliation are then permitted.
	5.	Authorizes a CP, following notification, "to reserve the right" to modify its Commitments for the duration of an upcoming three-year period "in accordance with" the procedures of this Article, and likewise authorizes retaliation.