Opinion

If a defendant requests a trial de novo following arbitration, and, due to court error, five years elapse before the trial de novo commences, may the action be dismissed for failure to comport with the five-year limitation of Code of Civil Procedure section 583?1

I.

The facts are not in dispute.

On March 6, 1975, real party in interest, Barbara Riccardo, filed an action for medical malpractice against petitioners, Dr. James Moran and the Santa Monica Hospital Medical Center (Hospital) in Los Angeles County Superior Court. During the next two years, the parties conducted extensive discovery proceedings which included interrogatories, requests for admissions and depositions.

On February 2, 1977, the at-issue memorandum was filed.2 Preparation of the case continued and on August 3, 1979, the certificate of readiness was filed, as required by the local rules.3 Subsequently, on October 11th, the court held a trial setting conference. At that time, the judge set a mandatory settlement conference for January 25, 1980, and a trial date of February 11, 1980.

*234At the settlement conference, the trial court determined that the amount in controversy did not exceed $15,000. With 17 days remaining until the scheduled start of trial, the court vacated the trial date and referred the case to arbitration. (See § 1141.11, subd. (a).4) When plaintiff’s attorneys expressed concern that the five-year period for bringing the case to trial would expire, the trial judge assured them that the statute would be tolled during arbitration (see § 1141.175) and that the case would be *235restored to the trial calendar should any party request a trial de novo following arbitration (see § 1141.20.6)

The case went to arbitration and after a full hearing in February and March of 1981, the arbitrator awarded Riccardo $12,000 on her claims against Moran. The arbitrator found against Riccardo as to the other defendants. When the arbitration award was filed on March 17, 1981, the limitations period provided by section 583(b) again commenced to run. At that time 41 days remained before expiration of the 5-year period. On April 3d, 24 days before the expiration of the 5-year period, Moran filed a request for a trial de novo.

*236Upon receipt of a copy of Moran’s request, Riccardo’s attorneys contacted the superior court clerk’s office by telephone. He requested that the case be reset for trial and given the same position on the trial calendar it had enjoyed prior to being referred to arbitration. (See § 1141.20, ante, fn. 6.) The clerk’s office assured the attorneys that the case would be reset within the five-year period. Although follow-up calls by Riccardo’s attorneys produced the same assurances, the clerk’s office sent the case file to the basement for storage.

The parties took no further action until August 12, 1981, when one of the defendants filed a motion to dismiss for violation of the five-year rule. The next day the trial court ordered a new trial setting conference to be held on September 22d. On August 28th, the Hospital filed its own section 583(b) motion to dismiss in which Moran subsequently joined.

On September 3, 1981, Riccardo opposed the motions to dismiss and moved to have the case specially set for trial or, alternatively, for judgment on the arbitration award. At this point, 129 days had elapsed since expiration of the 5-year period.

The motions to dismiss were heard and denied on September 18th, on the grounds that Riccardo had made a timely request for resetting following Moran’s request for a trial de novo and that the fault in not resetting the case lay with the court clerk. The judge denied Riccardo’s motion to set the case for trial on the ground that his department was not the proper one in which to file such a request.

Riccardo filed a new motion to specially set in the proper department which was heard on September 28, 1981. The motion was granted and the case was calendared for trial on October 14, 1981.

Before the trial commenced, defendants Moran, Storz, and the Hospital filed petitions for writ of mandate in the Court of Appeal to compel the trial court to dismiss the action. Proceedings in the lower court were stayed and on September 21, 1982, the Court of Appeal issued the requested writ ordering Riccardo’s action dismissed for failure to comply with the five-year rule. Her petition for hearing in this court followed.

II.

The sole issue presented by this proceeding is whether the trial court properly denied the section 583(b) motion to dismiss Riccardo’s malpractice action.7

*237Section 583(b) provides that a civil case “shall be dismissed” on motion of the defendant or the court if it is not brought to trial within five years after the action is filed.

The aim of section 583 is to “promote the trial of cases before evidence is lost, destroyed, or the memory of witnesses becomes dimmed . . . [and] to protect defendants from being subjected to the annoyance of an unmeritorious action remaining undecided for an indefinite period of time.” (General Motors Corp. v. Superior Court (1966) 65 Cal.2d 88, 91 [52 Cal.Rptr. 460, 416 P.2d 492]; Westinghouse Electric Corp. v. Superior Court (1983) 143 Cal.App.3d 95, 102 [191 Cal.Rptr. 549].)8

Despite the mandatory language of the section,9 this court has made an effort to “set[] reality above artificiality” in applying section 583(b). (Christin v. Superior Court (1937) 9 Cal.2d 526, 532 [71 P.2d 205, 112 A.L.R. 1153].) Implied exceptions to the rule have been recognized *238“where, for all practical purposes, going to trial would be impossible, whether this was because of total lack of jurisdiction in the strict sense, or because proceeding to trial would be both impracticable and futile.” (Chris-tin, supra, 9 Cal.2d at p. 533; accord General Motors, supra, 65 Cal.2d at p. 94; City of Pasadena v. City of Alhambra (1949) 33 Cal.2d 908, 916 [207 P.2d 17], cert. den. 339 U.S. 937 [94 L.Ed. 1354, 70 S.Ct. 671]; see also Bennett v. Bennett Cement Contractors, Inc. (1981) 125 Cal.App.3d 673, 676 [178 Cal.Rptr. 633].) The reasoning underlying these implied exceptions has been repeatedly noted. “The purpose of the statute is . . . to prevent avoidable delay for too long a period. It is not designed arbitrarily to close the proceeding at all events in five years. ...” (Christin, supra, 9 Cal.2d at p. 532, italics in original; accord Woley v. Turkus (1958) 51 Cal.2d 402, 406 [334 P.2d 12]; Rose v. Knapp (1951) 38 Cal.2d 114, 117 [237 P.2d 981]; Pacific Greyhound Lines v. Superior Court (1946) 28 Cal.2d 61, 67-68 [168 P.2d 665].)

What is impossible, impracticable or futile must be determined in light of all the circumstances in the individual case, including the acts and conduct of the parties and the nature of the proceedings themselves. (General Motors, supra, 65 Cal.2d at p. 96; Woley v. Turkus, supra, 51 Cal.2d at p. 407, Rose v. Knapp, supra, 38 Cal.2d at p. 117.) The critical factor in applying these exceptions to a £iven factual situation is whether the plaintiff exercised reasonable diligence in prosecuting his or her case.

The “reasonable diligence” standard is an appropriate guideline for evaluating whether it was impossible, impracticable, or futile for the plaintiff to comply with section 583(b) due to causes beyond his or her control. (See Westinghouse Electric, supra, 143 Cal.App.3d at p. 105.) Section 583(b) should not be applied to “penalizfe] conduct entirely reasonable” nor to impose a “procedure detrimental to the interest of both court and litigants.” (Christin, supra, 9 Cal.2d at p. 533.) Neither the courts nor litigants have any legitimate interest in preventing a resolution of the lawsuit on the merits if, through plaintiff’s exercise of reasonable diligence, the goals of section 583(b) have been met.

This “reasonable diligence” standard has already been adopted in several cases in which the application of section 583(b) has been at issue. (See Bennett, supra, 125 Cal.App.3d 673; Preston v. Kaiser Foundation Hospitals (1981) 126 Cal.App.3d 402 [178 Cal.Rptr. 882].) For example, in Bennett, the plaintiff had filed complaints against the defendant in two different counties in October of 1975. One of the cases was subsequently transferred to the county in which the other had been filed, and the cases were consolidated pursuant to the plaintiff’s request in April of 1979. The consolidated matters were set for trial to begin in August of 1979, one year *239and two months before the five-year statutory period had expired. The defendant’s successful motion to have the trial continued until October of 1979 was followed by six additional continuances on the court’s own motion on the grounds that no courtroom was available. When the matter was called for trial in February of 1981, the defendant moved to dismiss the case pursuant to section 583(b). The trial court granted the motion.

The Court of Appeal reversed the trial court’s judgment. It repeated the rule that “notwithstanding the apparently mandatory language of section 583, subdivision (b), it will not be applied in cases where it is impossible, impracticable or futile due to causes beyond a party’s control to bring an action to trial during the five-year period.” (Bennett, supra, 125 Cal.App.3d at p. 676.) The court found that the plaintiff had taken reasonable steps to secure a trial date, and had brought to the court’s attention at that time the fact that the five-year period was approaching.

Evaluating the facts of this case by the “reasonable diligence” standard delineated above, Riccardo’s conduct was sufficiently diligent to warrant application of the impossibility exception to excuse her failure to bring the case to trial within the five-year limit.

Riccardo’s action was commenced in March of 1975. Prior to the case being ordered to arbitration on January 25, 1980, she participated actively in an ongoing and thorough discovery process. Riccardo submitted requests for admissions, deposed Moran, and posed interrogatories to him and the other defendants. Riccardo’s motions to compel answers to the interrogatories and requests for admissions were argued. In addition, Riccardo offered her own deposition during this period and submitted to a physical examination by the defendants’ physicians. The names of Riccardo’s expert witnesses were provided to the defendants.

Riccardo participated in the six-day arbitration hearing. When Moran demanded a trial de novo following the arbitrator’s $12,000 award in Riccardo’s favor, she demonstrated continuing diligence by immediately contacting the master calendar clerk’s office and requesting that the matter be promptly reset for trial in order to meet the approaching five-year deadline. Follow-up telephone calls were made during the week of the request to ensure that the resetting process was in motion. The five-year deadline then passed while Riccardo was waiting for the case to be reset for trial.

*240Furthermore, Riccardo’s conduct met, at least in part, one of the goals of section 583(b)—to preserve the evidence necessary for trial before it is “lost, destroyed, or the memory of witnesses becomes dimmed.” (General Motors, supra, 65 Cal.2d at p. 91.) Riccardo’s continuing prosecution of her case by means of interrogatories, depositions and other discovery procedures adequately preserved the relevant evidence and testimony of the witnesses.

It is true that Riccardo took no further action on her request to reset the trial until after the first motion to dismiss was filed in early August of 1981. However, this conduct must be evaluated within the context of Riccardo’s previous actions. Riccardo had received assurances—from both the judge when the matter was ordered to arbitration and the court clerk’s office when the trial de novo was requested—that the matter would be reset within the five-year period. Further, Riccardo had vigorously prosecuted her case over a number of years before Moran requested the trial de novo. There can be no doubt of the diligence of her attempts to have the matter brought to trial. Consequently, Riccardo’s inactivity in the relatively short period following the request for a trial de novo detracts little from her showing of reasonable diligence in prosecuting this case.

Riccardo’s overall conduct during the five-year statutory period reflects her reasonable diligence in prosecuting the case. Therefore, the impossibility of Riccardo bringing her case to trial at the very end of this period due to the court’s failure to reschedule it warrants invoking the implied exception to mandatory dismissal pursuant to section 583(b).

The trial court properly found that she was entitled to have her case against Moran decided on the merits.

III.

Riccardo presents a second, independent argument for permitting her action to proceed. She contends that once Moran requested a trial de novo and the superior court was notified- that the five-year limit was rapidly approaching, it became the duty of the court to set the case for trial in a timely fashion. She maintains that the five-year period should have been tolled during the time it took the court to fulfill this duty.

The language of the arbitration statute itself confirms that Riccardo’s contention has merit. Section 1141.20 provides that, after the arbitrator’s decision has been filed, a party who is not satisfied with the award must initiate the process which will bring the case to trial by making a timely request for a trial de novo. Once such a request has been made, this *241section requires that a case be calendared for trial in the order of priority it held before arbitration. Since the trial court alone has the power to order a matter placed upon its trial calendar, section 1141.20 imposes a duty upon the court sua sponte to recalendar the trial in “the same place ... it had prior to arbitration. ”10 In compliance with this statutory mandate, and in order to ensure that the plaintiff will retain the benefit of the amount of time remaining in the five-year period when the case went into arbitration, that period will remain tolled until the new trial date set by the court.

Such a rule comports with this court’s holding in Hartman v. Santamarina (1982) 30 Cal.3d 762 [180 Cal.Rptr. 337, 639 P.2d 979]. In Hartman, the trial judge had been challenged under section 170.6.11 This motion was followed by an 11-month period of inaction in the case. The lack of action was attributable in part to the court’s failure to assign another judge to hear the case. In holding a dismissal under section 583(b) erroneous, this court noted that “ ‘the period that the trial is held in abeyance pending assignment of another judge is to be disregarded in considering a subsequent motion to dismiss.’” (Hartman, supra, 30 Cal.3d at pp. 767-768, quoting from Nail v. Osterholm (1970) 13 Cal.App.3d 682, 686 [91 Cal.Rptr. 908], italics added in Hartman.)

The rationale for tolling the five-year period following a section 170.6 motion was set forth by the court in the Nail case. After a section 170.6 challenge is allowed “it [is] the duty of a court to assign the case to another judge ... or if none is available to procure ... an outside judge through ... the Judicial Council. . . . [¶] . . . Consequently, plaintiff’s counsel was entitled to assume that official duty would be performed . . . .” Thus, Nail held that the time it took for the court to perform this duty would be *242excluded from the five-year period. (Nail, supra, 13 Cal.App.3d at pp. 686-688; accord Brown v. Engstrom (1979) 89 Cal.App.3d 513, 523-524 [152 Cal.Rptr. 628]; see also Weeks v. Roberts (1968) 68 Cal.2d 802 [five-year period tolled during period following trial court’s erroneous performance of duty].)

The same reasoning applies here. The five-year period elapsed while Riccardo was waiting for the trial court to perform its duty to recalendar the case for trial. Under these circumstances, section 1141.20 requires that the trial court return the action to the calendar in the same position for trial that it held before arbitration. Riccardo had a right to assume that the court would perform its duty so that her new trial date would stand in the same relation to the end of the five-year period as did her original trial date.

Where a defendant seeks a trial de novo after arbitration, the trial court should give the matter priority and assign it the earliest possible trial date. The time between the date the arbitration award is filed with the court and the date set for the new trial is to be excluded from calculation of the five-year period of section 583(b). This rule will ensure that the postarbitration trial date retains the same place in relation to the end of the five-year period as was held by the original trial date.

IV.

The trial court properly refused to dismiss Riccardo’s action under section 583(b) for two independent reasons. First, Riccardo had pursued her action with reasonable diligence so the court correctly found that the impossibility of Riccardo’s bringing her action to trial without a trial date invoked an implied exception to section 583(b). Second, dismissal of Riccardo’s action was premature because the time from the filing of the arbitration award until the new trial date of October 14, 1983, should have been excluded in calculating the five-year limit.12

Accordingly, the alternative writ of mandamus is discharged and the petitions for writ of mandamus are denied.

Mosk, J., Kaus, J., Broussard, J., Reynoso, J., and Grodin, J., concurred.

I concur on my understanding that part II of the court’s opinion does not intend to transplant the philosophy of Hocharian v. Superior Court (1981) 28 Cal.3d 714 [170 Cal.Rptr. 790, 621 P.2d 829] from section 581a of the Code of Civil Procedure—its former habitat—to subdivision (b) of section 583. Hocharian, of course, is generally understood to mean that in cases involving mandatory dismissals for failure to prosecute, the key issue is the plaintiff’s diligence, rather than the existence of a specific judicially developed exception or exceptions. As far as section 581a is concerned, the Legislature quickly amended that statute by adding subdivision (f) to nullify Hocharian (Stats. 1982, ch. 600, § 1, p. 2575).1 The exceptions allowed by that amendment are, of course, those which have long been judicially recognized as qualifying section 583, subdivision (b). The 1982 legislation is therefore not merely a repudiation of Hocharian, but an affirmation of preHocharian law with respect to section 583, subdivision (b).

While certain passages of part II of the court’s opinion are reminiscent of Hocharian, they are not necessarily at odds with the 1982 legislation. The opinion does rely on Westinghouse Electric Corp. v. Superior Court (1983) 143 Cal.App.3d 95, 105 [191 Cal.Rptr. 549], where there the Court of Appeal held: “[W]e believe reasonable diligence constitutes a guideline by which to assess the existing exceptions of impossibility, impracticability or futility. ” (My italics.) No one can quarrel with that formulation.

The facts depicted in the court’s opinion persuade me that under all the circumstances it was impracticable for plaintiff to bring the case to trial within the statutory period and that she was not guilty of such a lack of diligence as would estop her from claiming that the impracticability exception applies to her.

Grodin, J., concurred.