delivered the opinion of the court:
The issue common to these consolidated appeals is whether the record in each case evinces a valid waiver by the defendant of his right to a jury trial. Following a bench trial in the circuit court of La Salle County, the defendant in cause No. 59851, John K. Smith, was convicted of reckless conduct and sentenced to nine months’ imprisonment. The appellate court reversed that judgment and remanded the cause for a new trial (121 Ill. App. 3d 542), and we allowed the State’s petition for leave to appeal (94 Ill. 2d R. 315(a)). In cause No. 59911, the defendant, Green Flowers, was convicted in a bench trial in the circuit court of Cook County of two counts of battery and sentenced to concurrent 90-day terms of imprisonment. The appellate court affirmed that judgment (121 Ill. App. 3d 1158 (order under Supreme Court Rule 23 (87 Ill. 2d R. 23))), and we allowed the defendant’s petition for leave to appeal (94 Ill. 2d R. 315(a)). On our own motion we ordered the consolidation of the two appeals for oral argument and for disposition.
The facts of each case may be stated briefly. The record in cause No. 59851 discloses that the defendant, Smith, was charged by information on December 3, 1982, with the offense of reckless conduct; the charge alleged an occurrence in Mendota several months earlier, when the car that Smith was driving struck and injured a child. On December 4 Smith was served with a summons directing him to appear December 7 in the Mendota branch of the circuit court of La Salle County. Defense counsel filed an entry of appearance on December 7. The next item in the record is a notice dated December 21, 1982, informing Smith and his attorney that a bench trial was scheduled *332in this matter for February 2, 1983. On February 2 the information was dismissed on Smith’s motion; after a brief recess, more detailed informations were filed, charging Smith with reckless conduct and reckless driving. The matter then proceeded to a bench trial, and Smith was found guilty of both offenses. A summary of the proceedings held that day appears in the common law record, and it says in part, “Cause comes on for Bench Trial.” The trial judge later sentenced Smith to nine months’ imprisonment for reckless conduct and vacated the guilty finding for the other offense.
The appellate court reversed that judgment and remanded the cause for a new trial. With one justice dissenting, the appellate court agreed with Smith that the record failed to show that he had waived his right to a jury trial. Given that result, the court did not address the other arguments presented on appeal.
The record in cause No. 59911 discloses that the defendant, Flowers, was charged by complaint February 24, 1983, with two counts of battery, in addition to several other offenses; the charges alleged an occurrence on February 23, 1983, in which Flowers injured two police officers who were trying to arrest him. The first docket entry in the record is for' February 24, and it says simply, “MOTION STATE SET FOR 3-3-83 Call 2.” Similarly, the docket entry for March 3 says, “MOTION STATE SET FOR 3-10-83”; below that is the word “Final.” The next proceeding took place on March 10; a transcript reveals that on that day Flowers pleaded not guilty to the charges, the trial court heard and ruled on Flowers’ motion to suppress evidence, and the matter proceeded to trial, without a jury, and sentencing. The court found Flowers guilty of the two charges of battery and sentenced him to concurrent 90-day terms for those offenses. The sole evidence of a jury waiver is provided by entries in the half-sheets indicating the final dispositions of the *333charges; the entries are dated March 10, 1983. The two convictions bear a stamped legend that says in pertinent part, “TRIAL BY COURT-FINDING OF GUILTY.” The other charges bear a stamped legend that says in pertinent part, “PLEA OF NOT GUILTY JURY WAIVED.”
The appellate court affirmed the judgment. Finding the record on appeal incomplete, the appellate court concluded that Flowers had failed to present a sufficient basis for resolving his assertion that he had not made a valid waiver of his right to a jury trial.
The State argues at the outset that by not raising the validity of the jury waivers in post-trial motions both defendants have failed to preserve the issue for review. Defendant Flowers did not file a post-trial motion; defendant Smith filed one, but it did not include this issue. Nor was the question raised in either cause at any other time in the trial court. Normally, then, the issue would be deemed waived. (People v. McAdrian (1972), 52 Ill. 2d 250.) The waiver rule is one of administrative convenience rather than jurisdiction, however, and we have provided by rule that plain errors affecting substantial rights may be noticed on review though not brought to the trial court’s attention (87 Ill. 2d R. 615(a)). Without determining that in every case the sufficiency of a jury waiver will warrant review, we shall consider the issue as it is presented in the two causes here, given its importance and the frequency with which it arises. See People v. Rehbein (1978), 74 Ill. 2d 435, 439.
The right of an accused to a jury trial in a criminal prosecution is guaranteed by the Illinois Constitution. (111. Const. 1970, art. I, sec. 8.) Additionally, the defendants here had a similar right under the Federal Constitution (U.S. Const., amends. VI, XIV), for each was tried for a serious offense — one punishable by a term of imprisonment in excess of six months. Codispoti v. Pennsylvania (1974), 418 U.S. 506, 41 L. Ed. 2d 912, 94 S. *334Ct. 2687; Duncan v. Louisiana (1968), 391 U.S. 145, 20 L. Ed. 2d 491, 88 S. Ct. 1444.
Consistent with those constitutional requirements, section 103 — 6 of the Code of Criminal Procedure of 1963 (Ill. Rev. Stat. 1983, ch. 38, par. 103 — 6) provides:
“Waiver of Jury Trial. Every person accused of an offense shall have the right to a trial by jury unless understandingly waived by defendant in open court.”
To the same end, our decisions have imposed on the circuit courts the duty of ensuring that a defendant’s waiver of his right to a jury trial be made expressly and understanding^. (County of McLean v. Kickapoo Creek, Inc. (1972), 51 Ill. 2d 353; People v. Surgeon (1958), 15 Ill. 2d 236; People ex rel. Swanson v. Fisher (1930), 340 Ill. 250.) No set admonition or advice is required before an effective waiver of that right may be made, however. (People v. Frey (1984), 103 Ill. 2d 327; People v. Murrell (1975), 60 Ill. 2d 287; People v. Richardson (1965), 32 Ill. 2d 497.) Also, we have recognized the validity of a waiver made by defense counsel in the presence of the defendant and without his objection. Murrell; People v. Sailor (1969), 43 Ill. 2d 256.
Review of the validity of a defendant’s waiver of his right to a jury trial depends, of course, on the existence of an adequate memorial of the event, if it occurred at all. (People v. Chitwood (1977), 67 Ill. 2d 443.) Given the statutory requirement that a jury waiver be made in open court, a suitable report of the proceeding in which the waiver is supposed to have occurred will be an essential part of the record in an appeal that raises the question. The necessary report ‘may take any one of several forms — our rules provide that if a verbatim transcript of a proceeding is not available, a party may submit in its stead a proposed report of proceedings or an agreed statement of facts. (87 Ill. 2d Rules 323(c), 323 (d), 612(c); People v. Hopping (1975), 60 Ill. 2d 246.) Responsibility *335for preserving and presenting a sufficient record of the asserted error necessarily falls on the party who makes the assertion of error. (People v. Edwards (1978), 74 Ill. 2d 1; People v. Smith (1969), 42 Ill. 2d 479.) Therefore, when an entry in the common law record indicates that a jury waiver has been made, a defendant seeking review of that question should include in the record on appeal a transcript, or suitable substitute for one, of the corresponding proceeding. Only by that means can a court of review determine whether the entry in the record reflects a valid jury waiver. In People v. Oatis (1977), 47 Ill. App. 3d 229, 232, the court correctly observed:
“[I]n a criminal case when the common law record shows that the defendant has waived jury trial, on appeal after a bench trial, a defendant claiming error in the jury waiver must cite the specific error that occurred and substantiate that claim by the presentation of a sufficient record. If the claim is that the jury waiver was not made in open court or that it was not understandingly made, the record should be sufficient to cover all proceedings which involved the waiver.”
If the State believes that the jury waiver was made on an occasion other than that suggested in the record, then the record may be supplemented, at the State’s request, with the corresponding report.
Applying these rules to cause No. 59851, we conclude that defendant Smith has failed to present an adequate record from which the validity of his jury waiver may be determined. The waiver of his right to a jury trial occurred, if at all, on December 7, 1982. The record before us shows that on that day the defendant was scheduled to appear and, also, that his attorney filed an appearance. We allowed the State’s motion to supplement the record on appeal with the record sheets maintained in this cause by the circuit court clerk. The entries on the record sheets reflect generally what is contained in the *336common law record and in the transcripts of the trial and post-trial proceedings. Notably, the entry for December 7 says, “Attorney Reck entered his appearance to be sent to Ottawa for Bench trial before Judge Wimbiscus.” No report of the proceedings for December 7 — if any were held that day — is included in the record. Thus, we have no way of determining whether a valid waiver was or was not made that day. It was Smith’s duty here, as the party appealing the circuit court judgment, to preserve and present on review an adequate record from which his allegation of error could be resolved. Without that, we must assume that the record indications of a jury waiver are indeed based on a valid waiver.
In cause No. 59911, we conclude that the record is sufficient and that it fails to show that defendant Flowers made a valid waiver of his right to a jury trial. There, the only indication that Flowers waived his right to a jury trial appears in the half-sheet entries for March 10; the transcript of the proceedings held that day is silent on the subject.
Although the March 10 entries contain the earliest references in the common law record to a jury waiver, the State believes that Flowers should have included in the record on appeal reports of the proceedings held in this cause on February 24 and March 3. The State believes that a valid jury waiver might have been made on those other occasions and therefore contends that regardless of the half-sheet entries for March 10, Flowers’ failure to include in the record on appeal reports of the earlier proceedings is fatal.
The entries on the half-sheets indicate that the jury waiver was made, if at all, on March 10. The entries for the two earlier proceedings, occurring February 24 and March 3, are silent in this regard, and we reject the State’s argument that Flowers was required to submit reports of those earlier proceedings. We conclude that, *337for the purpose of resolving the question whether a valid jury waiver was made, Flowers preserved and presented to the appellate court a sufficiently complete record of the circuit court proceedings. The sufficiency of the record is borne out, incidentally, by the verbatim transcripts of the earlier proceedings, which Flowers was allowed to file in this court as a supplement to the record on appeal. According to the two transcripts, on February 24 Flowers appeared with counsel, bond was set, and defense counsel made a demand for trial; the cause was then continued until March 3, when it was passed at the State’s request and not recalled on that day.
It is apparent from the record, then, that the requirements of an understanding waiver made in open court were not satisfied, and therefore the cause must be remanded for a new trial. See County of McLean v. Kickapoo Creek, Inc. (1972), 51 Ill. 2d 353; People v. Montgomery (1981), 96 Ill. App. 3d 994; People v. Coleman (1978), 59 Ill. App. 3d 1050.
Accordingly, in cause No. 59851, we reverse the judgment of the appellate court; as other issues were raised there but not decided, we remand the cause to that court for further proceedings. In cause No. 59911, we reverse the judgments of the appellate and circuit courts and remand the cause to the circuit court for a new trial.
59851 — Judgment reversed; cause remanded.
59911 — Judgments reversed; cause remanded.