opinion of the Court.
¶ 1 Agreements between parties or attorneys in civil lawsuits are not binding if disputed unless they are evidenced by a writing or made orally in court. Ariz. R. Civ. P. 80(d). We here consider whether Rule 80(d) makes a written settlement agreement unenforceable because it lacked the written assent of clients who dispute their attorney’s authority to make the agreement. Holding that no such written assent is required and that the agreement here satisfied Rule 80(d), we also conclude that it is enforceable because the attorney acted within the apparent authority given by his clients.
I. BACKGROUND
¶ 2 Petitioners (“the Robertson Group”) sued neighboring property owners (“the Ailing Group”) concerning a water line. On January 29, 2013, the parties and their attorneys attended a mediation but did not reach an agreement. At the end of the mediation, the Ailing Group, represented by attorney Mark Sifferman, made a settlement offer requiring acceptance within forty-eight hours.
¶ 3 Sifferman advised his clients of Grasso’s request and recommended they “leave the door open” for settlement. Two of the Ailing Group members emailed Sifferman on February 4 stating that they and others favored “removing the settlement offer proposed
¶ 4 On February 6, after talking with another attorney at Grasso’s law firm, Sifferman sent that attorney an email extending a new settlement offer with terms that mirrored the prior offer but would expire at 5:00 p.m. on February 8. Grasso timely accepted the offer via email. Later, after Grasso’s law firm had informed the trial court of the settlement (the “February 8 settlement”) and circulated draft settlement documents, Sifferman discovered he had lacked authority to extend the settlement offer. After conferring with his clients, Sifferman made a new settlement offer, which materially varied from the February 8 settlement.
¶ 5 The Robertson Group moved to enforce the February 8 settlement. Without an evidentiary hearing, the trial court granted the motion, ruling that Sifferman had actual and apparent authority to extend the settlement offer and, alternatively, that the Ailing Group was equitably estopped from disputing that authority. The court also ruled that Arizona Rule of Civil Procedure 80(d) did not apply but, if it did, the emails exchanged between counsel satisfied the rule.
¶ 6 The court of appeals reversed. Robertson v. Ailing,
¶ 7 We granted review to decide whether Rule 80(d) applies when an attorney’s authority to settle is challenged and to provide guidance on apparent authority, both recurring issues of statewide importance. We have jurisdiction pursuant to Article 6, Section 5 of the Arizona Constitution.
II. DISCUSSION
¶ 8 Because the trial court effectively granted summary judgment regarding the existence, terms, and enforceability of the parties’ settlement agreement, we employ the summary judgment standard of review. See Perry v. Ronan,
A. Rule 80(d)
¶ 9 Rule 80(d) provides that “[n]o agreement or consent between parties or attorneys in any matter is binding if disputed, unless it is in writing, or made orally in open court, and entered in the minutes.” The issue before us is whether the rule requires a writing reflecting a client’s assent to a written agreement when the client disputes its attorney’s authority to make the agreement.
¶ 10 We interpret court rules to effect the drafters’ intent. State v. Salazar-Mercado,
¶ 11 The Robertson Group relies on Hays v. Fischer as support for its argument that Rule 80(d) applies only if “the existence of the settlement agreement and its terms are ... in dispute” and not when the client disputes whether it is bound by the settlement agreement.
¶ 12 Like the court of appeals, see Robertson,
¶ 13 We agree with the Robertson Group. Rule 80(d) serves to avoid collateral disputes between parties by requiring written evidence of any stipulations and agreements. Cf. Hackin v. Rupp,
¶ 14 But even if Rule 80(d) applies, the attorneys’ exchange of emails satisfied the rule. Nothing requires clients to separately assent in writing to a written agreement brokered by their attorney. Construing Rule 80(d) to require the client’s assent when the client disputes its attorney’s authority would abrogate the apparent authority doctrine in the attorney-client context. Our courts have long recognized that attorneys can bind clients who have cloaked them with apparent authority to act on their behalf. See, e.g., Panzino v. City of Phoenix,
¶ 15 We endorse the holding in Hays that Rule 80(d) applies only when parties dispute the existence or terms of an agreement, as distinct from other challenges to its enforceability. If such a dispute exists, the rule can by satisfied by writings exchanged between counsel. Rule 80(d) does not require the client’s written assent to the agreement. We disapprove Canyon Contracting insofar as it reached a different conclusion. Because the parties do not dispute the existence or terms of the February 8 settlement, Rule 80(d) does not preclude its enforcement.
B. Apparent Authority
¶ 16 The relationship between an attorney and client is governed by agency law principles. See Panzino,
¶ 17 An attorney without actual authority to settle a dispute can nevertheless do so if the other party to the agreement “reasonably assumes that the lawyer is authorized to do the act on the basis of the client’s (and not the lawyer’s) manifestation of such authorization.” Restatement (Third) of Law Governing Lawyers § 27; Restatement (Third) of Agency § 3.03 (to same effect). The client “manifests assent or intention through written or spoken words or other conduct.” Restatement (Third) of Agency § 1.03. That the client has retained an attorney does not establish apparent authority to settle a dispute. See United Liquor Co. v. Stephenson,
¶ 18 The undisputed facts establish Sifferman’s apparent authority to bind the Ailing Group to the February 8 settlement. At the end of the mediation, all members of the Ailing Group, after consulting with their attorneys, offered, through the mediator, to settle the lawsuit on specified terms. The attorneys for each side, at the mediator’s suggestion, immediately met without their clients to “hash out” the settlement terms. At Grasso’s request, Sifferman agreed to leave the offer open for forty-eight hours to enable Grasso to expedite discussions with the Robertson Group’s insurers concerning payment of the group’s attorney fees. Although the deadline initially requested by Grasso expired, Sifferman confirmed days later that the offer remained available on the same terms, and the Robertson Group accepted it.
¶ 19 By extending a settlement offer and then leaving Sifferman to finalize the timing and terms, the Ailing Group manifested its intention that Sifferman was empowered to conclude the settlement on the terms approved by the Ailing Group. The forty-eight-hour deadline was not part of the offer extended by the Ailing Group. Rather, Grasso requested the deadline for the benefit of the Robertson Group, Sifferman agreed to it without consulting the Ailing Group, and nothing suggested that the deadline was material to the Ailing Group. Without a deadline, the offer would have expired after a reasonable time period, unless revoked. 1 Williston on Contracts § 5:2 (4th ed.) (2015). By initially granting Grasso’s request for a forty-eight-hour deadline and then effectively extending the offer as “still open” days after the deadline expired, Sifferman acted within his apparent authority to complete the settlement on the terms agreed to by the Ailing Group. Cf. Restatement (Third) of Law Governing Lawyers § 21(3) (stating that absent client instruction or agreement, “a lawyer may take any lawful measure within the scope of representation that is reasonably calculated to advance a client’s objectives as defined by the client”).
¶ 20 In sum, we hold that the Ailing Group’s actions allowed the Robertson Group to reasonably assume that Sifferman had authority to keep a settlement offer on the table or reoffer the same settlement terms days after the agreement’s expiration, and the Robertson Group reasonably relied on the attorney’s apparent authority. Therefore, we agree with the trial court that the settlement agreement is binding on the Ailing Group.
C. Attorney Fees
¶ 21 The Robertson Group requests attorney fees pursuant to A.R.S. § 12-341.01, which gives courts discretion to award fees “[i]n any contested action arising out of a contract.” Because enforcement of the February 8 settlement is such an action, we award the Robertson Group its reasonable attorney fees expended on appeal upon its compliance with ARCAP 21(b).
III. CONCLUSION
¶ 22 Rule 80(d) applies only if a party disputes the existence or terms of an agreement. If such a dispute exists, the rule can be satisfied by writings exchanged by counsel. Rule 80(d) does not also require the written assent of a client who disputes that it
Notes
. Another attorney represented one member of the Ailing Group. That member is not a party here, and the acts of that member and her attorney are not at issue.
