with whom WINFREE, Justice, joins, dissenting in part.
Justin and Erica Nelson divorced in 2008 and entered into a Parenting Agreement governing their two children. Their agreement, which was adopted by the superior court, provided for shared legal and physical custody while both parents lived near Fairbanks. The agreement also expressly anticipated a move from Fairbanks by one or both parents, and set forth custody arrangements for that eventuality.
In February 2009, Justin sought modification of custody on the grounds that he would soon relocate to the continental United States. A hearing was held, after which the superior court denied Justin's motion to modify custody. The superior court found that the parties' Parenting Agreement contemplated the upcoming move, and interpreted the agreement to provide school-year custody to Erica, the non-moving parent. The court today vacates the superior court's order and remands for a best-interests assessment. Because I would affirm the superior court's decision, I dissent in part.1
A. The Parties Agreed Upon, And The Superior Court Adopted, The Parenting Agreement Dictating The Custody Arrangement In The Event That One Parent Relocates.
In its opinion, the court concludes that "n our view, Justin and Erica did not agree upon a final custody arrangement in the event that one parent relocates."
*55In my view, the Nelsons agreed upon precisely this. The Parenting Agreement anticipated that a parent would move away from Fairbanks and detailed custody arrangements to take effect in that case. Paragraph 11 of the Agreement states that "[ilf in the future the parents don't reside in the same community, they agree one parent will have the children for the school year and the other parent will have the children for summers and some school breaks.... [Also,] no changes of custody between parents' homes will occur during a school year." 2 Paragraph 12 goes on to provide that:
If a parent moves in the future, which the parents agree will occur eventually, they will have to create a parenting agreement for different communities Until they have that agreement the children cannot be moved. from their current community. But the children will have visits with the moving parent during breaks from school, as follows, until an updated agreement is reached:
a. Summers, starting from a week after school is out until two weeks before school resumes;
b. Alternate winter breaks....
e. Alternate spring breaks....
(Emphasis added.)
The Nelsons contemplated and, in the Parenting Agreement, specifically prepared for the eventuality that one of the parties would move from Fairbanks. I would construe their Agreement as the superior court did, namely to provide that in the event of a move, Justin and Erica "agreed that the non-moving parent would retain custody for the school year." 3
B. There Has Been No Change In Circumstances Warranting Custody Modification.
The superior court found no change in circumstances because one parent's move from Fairbanks was not only anticipated but explicitly planned for in the custody agreement.4 I would affirm the superior court's decision in this regard.
To modify a custody award, "[the parent seeking modification must first establish that there has been a 'significant change in circumstances affecting the child's best interests.'"5 We have held that as a matter of law, one parent's relocation out of Alaska constitutes a significant change in circumstances.6 This triggers a hearing on the children's best interests.7
But we also have stated that a change in cireumstances "must be demonstrated relative to the facts and cireumstances that existed at the time of the prior custody order that *56the party seeks to modify."8 Here, both parties clearly contemplated and planned for one parent's move.
Moreover, courts should "avoid disturbing and upsetting [children] with repeated custody changes."9 "[The change in circumstances requirement is intended to discourage continual relitigation of custody decisions, a policy motivated by the judicial assumption that finality and certainty in custody matters are critical to the child's emotional welfare." 10 In other words, a custody situation that has been settled-such as the custody arrangement accompanying an upcoming move-should not be revisited unless the situation has notably changed, and the parents' mere belief or agreement that relitigation is necessary is insufficient to trigger modification of an award.11
I would therefore affirm the superior court's conclusion that no change of cireum-stances exists sufficient to warrant modification of custody.
C. The Superior Court Did Not Err In Enforcing The Parenting Agreement.
The court notes that the superior court is not bound by the Parenting Agreement, and concludes that the superior court erred by modifying custody without undertaking a best-interests analysis.
But the superior court did not modify custody at all-it simply enforced the parties existing, court-approved Parenting Agreement. The Nelsons may have reached their Parenting Agreement by way of settlement and without counsel, but it is apparent that they worked with the Fairbanks trial court's child custody negotiators to come to their agreement: these kinds of settlements are encouraged by the legislature and by this court,12 and the superior court specifically "approved" the Agreement in its Findings and Conclusions for the divorce.13
Stipulated custody arrangements are of course subject to modification under the changed cireumstances doctrine.14 But in my view it should take more than one parent's move from Fairbanks-a specific eventuality that the parties contemplated and planned for-to show a substantial change in cireumstances to modify the custody arrangement set out in this Parenting Agreement.
The court today pays little heed to the parties' agreement, and finds instead that when parents agree on a custody arrangement that contemplates an upcoming move-even when this agreement has been explicitly adopted by the superior court-one parent can still invoke this same upcoming move as a changed cireumstance for custody modification purposes. In my view this conclusion is incorrect, and also stretches the meaning of "changed cireumstance" too far. What is the point of explicitly providing for foreseeable changes in a custody agreement if the foreseen move will trigger a new best interests analysis?
D. Conclusion
The Nelsons' Parenting Agreement re-fleets careful consideration of the children's *57best interests in stability; it also expressly contemplates a move by one parent from Fairbanks and the parties agreed upon custody arrangements when this occurred. I agree that remand for determination of the custody investigator fee is appropriate, but because I would affirm the superior court's order declining to modify custody and enfore-ing Justin and Erica's Parenting Agreement, I respectfully dissent in part.
. I agree with the court that the issue of payment of the custody investigator's fees must be remanded for consideration.
. Paragraph 11 also references a "#6." Paragraph 6 concerns travel for church or school activities. Justin asserts that "# 6" in fact references a nonexistent section. In either event, it does not modify the meaning of paragraph 11 as executed.
. The court relies on the fact that the Parenting Agreement stipulates that a new agreement will need to be reached if a parent moves from Fairbanks. But the language in paragraph 12 seems limited to logistical modifications, not to the underlying premise that custody would stay with the parent in Fairbanks. But even if paragraph 12 is not so limited, the fact that the parents agreed that they would at some point have to create a new parenting agreement in the future in no way invalidates their agreement that the nonmoving parent would retain principal custody of the children during the school year.
. The superior court characterized the Agreement as providing that Justin and Erica "anticipated movement by one or both parents, and agreed that the non-moving parent would retain custody for the school year."
. Williams v. Barbee, 243 P.3d 995, 1000 (Alaska 2010) (quoting Eberfz v. Eberfz, 113 P.3d 643, 647 (Alaska 2005)); see also Peterson v. Swarth-out, 214 P.3d 332, 340 (Alaska 2009) (quoting J.L.P. v. V.L.A., 30 P.3d 590, 595 (Alaska 2001) ("Under AS 25.20.110(a), a court may modify custody only if it finds 'a change in circumstances' that is 'significant or substantial.' "); House v. House, 779 P.2d 1204, 1207 (Alaska 1989).
. Barbee, 243 P.3d at 1000 (citing Chesser-Wit-mer v. Chesser, 117 P.3d 711, 717 (Alaska 2005) (explaining that a change of circumstances "exists as a matter of law when a custodial parent [including a parent with joint custody] moves out of state").
. McQuade v. McQuade, 901 P.2d 421, 424 n. 6 (Alaska 1995).
. Peterson, 214 P.3d at 341 (quoting Jenkins v. Handel, 10 P.3d 586, 589 (Alaska 2000)) (internal quotation omitted); see also King v. King, 477 P.2d 356, 359 (Alaska 1970) (quoting Houger v. Houger, 449 P.2d 766, 773 (Alaska 1969) (concluding that a superior court is "justified in modifying ... custody arrangements only if it had been shown that since the date of entry of the judgment changed facts and circumstances affecting the welfare of the children required modification for the best interests of the children.").
. McLane v. Paul, 189 P.3d 1039, 1043 (Alaska 2008) (citing SN.E. v. R.L.B., 699 P.2d 875, 878 (Alaska 1985)).
. Peterson, 214 P.3d at 340-41 (quoting Gratrix v. Gratrix, 652 P.2d 76, 82-83 (Alaska 1982) (internal quotation marks omitted)).
. See Morino v. Swayman, 970 P.2d 426, 428 (Alaska 1999) (requiring that the movant prove a substantial change as a threshold to custody modification).
. See Crane v. Crane, 986 P.2d 881, 888-89 (Alaska 1999).
. It was at that point that if questions about the children's best interests were raised, the superior court had the discretion to inquire further before adopting and approving the Agreement. Crane, 986 P.2d at 889.
. Crane, 986 P.2d at 889 n. 4 (citing Garding v. Garding, 767 P.2d 183, 185 (Alaska 1989)).