JUSTICE HUTCHINSON delivered the opinion of the court:

This matter comes before the court as an interlocutory appeal brought pursuant to SupremeCourt Rule 308 (155 Ill. 2d R. 308). Plaintiff, Corinne Thompson, individually and as independentadministrator of the estates of Trevor Thompson and Amber Thompson, both deceased, appeals thetrial court's order striking the affidavit of her retained opinion witness, Andrew Ramisch, an engineernot licensed in the State of Illinois. For the reasons that follow, we decline to answer the firstcertified question, we answer the second certified question, and we reverse and remand.

Following a fatal motor vehicle collision in Gurnee that occurred in November 1998, plaintiffinitiated a cause of action against defendants, Christie Gordon, Grand Avenue Properties, Inc.,Gurnee Mills (MLP) Limited Partnership, f/k/a Gurnee Mills Limited Partnership, Gurnee PropertiesAssociated Limited Partnership, Western Development Corporation, Jack E. Leisch & Associates,Inc. (Leisch), CH2M Hill, Inc. (CH2M), The Mills Corporation, The Mills Limited Partnership,Gurnee Mills II LLC, and Gurnee Mills LLC. As amended, plaintiff's complaint included allegationsof improper roadwork at or near the accident site. Plaintiff alleged that defendants, specifically Leischand CH2M, had a duty to exercise reasonable care in designing the roadway near the accident siteand that their failure to do so proximately caused plaintiff's injuries and the deaths of Trevor andAmber Thompson.

In November 2002, defendants Leisch and CH2M moved for summary judgment (see 735ILCS 5/2--1005 (West 2002)). In response to their motion, plaintiff submitted the affidavit ofAndrew Ramisch, plaintiff's expert opinion witness retained pursuant to Supreme Court Rule 213(177 Ill. 2d R. 213). According to his curriculum vitae, Ramisch is a civil engineer, licensed in theDistrict of Columbia, with approximately 30 years' experience in the analysis, design, and constructionof roadways. In his affidavit, Ramisch opined that CH2M failed to meet the standard of care indesigning the roadway that was at or near the site of the accident. Thereafter, in January 2003,defendants Leisch and CH2M moved the trial court to strike Ramisch's affidavit, arguing thatRamisch was not qualified to render a professional opinion because he was not licensed as aprofessional engineer in Illinois pursuant to the Illinois Professional Engineering Practice Act of 1989(the Engineering Act) (225 ILCS 325/1 et seq. (West 2002)). Defendants relied on this court'sopinion in Van Breemen v. Department of Professional Regulation, 296 Ill. App. 3d 363 (1998), insupport of their motion to strike.

The trial court conducted a hearing and, following the arguments of the parties, granteddefendants' motion to strike. In September 2003, plaintiff moved to reconsider the trial court'sdecision to strike Ramisch's affidavit. The trial court denied plaintiff's motion to reconsider butgranted plaintiff's subsequent motion for interlocutory appeal pursuant to Supreme Court Rule 308(155 Ill. 2d R. 308), and certified the following questions:

"Whether the work of an engineer, unlicensed in the State of Illinois, as an IllinoisSupreme Court Rule 213(f) retained opinion witness in a litigated matter in the State ofIllinois, constitutes the unlicensed practice of professional engineering under the IllinoisProfessional Engineering Act (225 ILCS 325/1 (1992))"; and

"Whether Van Breemen v. Department of Regulation, 296 Ill. App. 3d 363 *** (2ndDist. 1998) controls the issue of whether a trial court strikes, on motion, the affidavit of anIllinois Supreme Court Rule 213(f) retained opinion witness, retained in a litigated matter inthe State of Illinois, where the opinion witness is not licensed in the State of Illinois."

Plaintiff timely filed an application for leave to appeal, and this court granted the application. Wenow address the certified questions presented, reverse the trial court's order, and remand.

This court's examination in an interlocutory appeal is strictly limited to the questions certifiedby the trial court and, as with all questions of law, is a de novo review. In re Consolidated Objectionsto Tax Levies of School District No. 205, 306 Ill. App. 3d 1104, 1107 (1999), citing Lanxon v.Magnus, 296 Ill. App. 3d 377, 379 (1998). Thus, our task is to answer the certified questions ratherthan to rule on the propriety of any underlying order. P.J.'s Concrete Pumping Service, Inc. v. NextelWest Corp., 345 Ill. App. 3d 992, 998 (2004), citing Danner v. Norfolk & Western Ry. Co., 271 Ill.App. 3d 598, 601 (1995). In the interests of judicial economy and reaching an equitable result,however, a reviewing court may go beyond the certified questions and consider the appropriatenessof the order giving rise to the appeal. P.J.'s Concrete Pumping Service, 345 Ill. App. 3d at 998-99,citing Bright v. Dicke, 166 Ill. 2d 204, 208 (1995).

In the present case, the first question we are called upon to consider is whether the work ofan engineer who is retained as a Rule 213(f) opinion witness constitutes the unlicensed practice ofprofessional engineering under the Engineering Act when the engineer is unlicensed in Illinois. Weare unable to answer this first question for a number of reasons. First, the parties do not attempt toexplain how the first question involves a question of law that is governed by conflicting authority, andsecond, they do not explain how entertaining an immediate appeal of this question will materiallyadvance the ultimate termination of the litigation. See 155 Ill.2d R. 308(a). These insufficienciesrender the first question unsuitable for our review.

Third, and perhaps most important, the initial determination of what constitutes the unlicensedpractice of engineering in Illinois is relegated, not to the appellate court, but to the Department ofProfessional Regulation. See 20 ILCS 2105/2105--1 et seq. (West 2002); 225 ILCS 325/1 et seq.(West 2002). In section 5--15 of the Civil Administrative Code of Illinois (20 ILCS 5/5--15 (West2002)), the legislature created the Department of Professional Regulation (the Department) as adepartment of state government. In article 2105 of the Civil Administrative Code of Illinois (theDepartment of Professional Regulation Law) (20 ILCS 2105/2105--1 et seq. (West 2002)), thelegislature set out the powers and duties of the Department. In section 2105--10 of the Departmentof Professional Regulation Law, the legislature declared:

"The practice of the regulated professions *** is hereby declared to affect the publichealth, safety, and welfare of the People of this State and in the public interest is subject toregulation and control by the Department of Professional Regulation.

It is further declared to be a matter of public interest and concern that standards ofcompetency and stringent penalties for those who violate the public trust be established toprotect the public from unauthorized or unqualified persons representing one of the regulatedprofessions ***." 20 ILCS 2105/2105--10 (West 2002).

The powers and duties of the Department include passing upon the qualifications of applicants forlicenses; conducting hearings or taking other disciplinary action as authorized in any licensing actadministered by the Department with regard to licenses of persons exercising the respectiveprofessions; and formulating rules and regulations for the enforcement of any act administered by theDepartment. See 20 ILCS 2105/2105--15 (West 2002). In section 2105--75 of the Department ofProfessional Regulation Law (20 ILCS 2105/2105--75 (West 2002)), the legislature specificallyestablished "design professionals dedicated employees," who "shall be devoted exclusively to theadministration and enforcement" of, among others, the Engineering Act (225 ILCS 325/1 et seq.(West 2002)).

Accordingly, the Engineering Act is a legislative enactment created under the aegises of theDepartment of Professional Regulation Law and the Civil Administrative Code of Illinois. See 20ILCS 5/5--15 (West 2002); 20 ILCS 2105/2105--10 (West 2002). The Engineering Act provides forthe comprehensive regulation of the practice of professional engineering and sets forth, inter alia,definitions and examples of the practice of professional engineering; educational qualifications forprofessional engineers; authorization for an agency charged with administering the provisions of theEngineering Act; provisions for the examination of qualified applicants; and provisions for disciplineand punishment. 225 ILCS 325/1 et seq. (West 2002); Miller v. Department of ProfessionalRegulation, 276 Ill. App. 3d 133, 137 (1995). To be more specific, section 5 of the Engineering Actprovides in relevant part:

"Subject to the provisions of this Act, the Department [of Professional Regulation]shall exercise the following functions, powers and duties:

(a) To pass upon the qualifications and conduct examinations of applicants forlicensure ***.

(d) To conduct investigations and hearings regarding violations of this Act andtake disciplinary or other actions as provided in this Act as a result of the proceedings.

***

(f) To promulgate rules required for the administration of this Act, includingrules of professional conduct." 225 ILCS 325/5 (West 2002).

Section 24(a) of the Engineering Act provides that the "Department shall adopt rules settingstandards of professional conduct and establish appropriate penalty for the breach of such rules." 225ILCS 325/24(a) (West 2002). Following an administrative decision rendered in a particular caseaffecting the legal rights, duties, or privileges of a party, this court may entertain an appeal broughtpursuant to the Administrative Review Law (735 ILCS 5/3--101 et seq. (West 2002)). 225 ILCS325/37 (West 2002).

In the present case, defendants Leisch and CH2M moved the trial court to strike Ramisch'saffidavit based on his lack of an Illinois license. The first certified question asks whether the workof an engineer who is retained as an opinion witness constitutes the unlicensed practice ofprofessional engineering under the Engineering Act when the engineer is unlicensed in Illinois. Onour review of the Civil Administrative Code of Illinois, the Department of Professional RegulationLaw, and the Engineering Act, this reviewing court does not act in an administrative capacity to makesuch determinations. Rather, we believe it is within the province of the Department of ProfessionalRegulation to determine what constitutes the unlicensed practice of professional engineering underthe Engineering Act. Accordingly, we decline to answer the first certified question. See Dowd &Dowd, Ltd. v. Gleason, 181 Ill. 2d 460, 470 (1998) (declining to answer a certified question giventhe provisional nature of the inquiry, the importance of the issue involved, and the absence of a fullydeveloped factual record).

The second certified question asks whether Van Breemen, 296 Ill. App. 3d 363, controls theissue of whether a trial court strikes, on motion, the affidavit of a Rule 213(f) retained opinion witnesswho is not licensed in the State of Illinois. In Van Breemen, the Department of ProfessionalRegulation solicited from the plaintiff a brochure that advertised his services as an expert witness. The plaintiff responded, detailing his education and work experience, which included engineeringdesign, product development, failure analysis, and investigative procedure, and accentuating hisforensic work and industrial-failure investigations. Van Breemen, 296 Ill. App. 3d at 366. Thereafter, the Department initiated a rule to show cause against the plaintiff to cease and desist fromthe unlicensed practice of professional engineering. Van Breemen, 296 Ill. App. 3d at 364. Following the receipt of the plaintiff's answer to the rule, the Department found that the plaintiff hadfailed to answer the rule to its satisfaction, and it concluded that the plaintiff was engaged in theunlicensed practice of professional engineering. Van Breemen, 296 Ill. App. 3d at 364-65. TheDepartment ordered the plaintiff to cease and desist from the unlicensed practice of professionalengineering. Van Breemen, 296 Ill. App. 3d at 365. The plaintiff then brought a complaint forjudicial review of the administrative decision, and the trial court affirmed the Department's cease anddesist order. Van Breemen, 296 Ill. App. 3d at 365. In affirming the trial court's judgment, wereviewed, inter alia, the sufficiency of the Department's findings and the validity of its conclusions.

The Van Breemen decision has nothing to do with the issue of whether a trial court shouldstrike the affidavit of a retained opinion witness. The Van Breemen decision did not reflect on theplaintiff's competency as an engineer. It had nothing to do with his qualifications as a retained expertwitness. The issue of whether the plaintiff in Van Breemen was competent to act as an expert wasnot even before the reviewing court. Rather, Van Breemen was a judicial review, following a ceaseand desist order, of an administrative agency's findings and decision that the plaintiff had violatedprovisions of the Engineering Act by holding himself out as a professional engineer and offering toperform professional engineering services, especially forensic engineering. The present case,however, comes to this court, not on judicial review of an administrative decision, but, rather, on aruling to strike the affidavit of an expert opinion witness. Furthermore, Ramisch is a professionalengineer--and duly licensed--only not in this state. Accordingly, we determine that the Van Breemencase does not control the issue of whether a trial court strikes, on motion, the affidavit of a Rule213(f) retained opinion witness, where the opinion witness is not licensed in the State of Illinois. Wetherefore answer the second certified question in the negative.

In Snelson v. Kamm, 204 Ill. 2d 1 (2003), our supreme court discussed the applicable lawregarding expert witnesses, stating:

"The decision of whether to admit expert testimony is within the sound discretion ofthe trial court [citation], and a ruling will not be reversed absent an abuse of that discretion[citation]. Expert testimony is admissible if the proffered expert is qualified by knowledge,skill, experience, training, or education, and the testimony will assist the trier of fact inunderstanding the evidence. [Citation.]" Snelson, 204 Ill. 2d at 24.

Expert testimony therefore is proper if the evidence offers " 'knowledge and application of principlesof science beyond the ken of the average juror.' " Zavala v. Powermatic, Inc., 167 Ill. 2d 542, 546(1995), quoting Plank v. Holman, 46 Ill. 2d 465, 471 (1970).

In the present case, defendants Leisch and CH2M moved the trial court to strike Ramisch'saffidavit, arguing that Ramisch was not qualified to render a professional opinion because he was notlicensed as a professional engineer pursuant to the Engineering Act. The record reflects that Ramischis a civil engineer, licensed in the District of Columbia, with approximately 30 years' experience in theanalysis, design, and construction of roadways. Licensure with the State of Illinois pursuant to theEngineering Act is not required to render an expert opinion; rather, the witness must be deemed tobe an "expert," or have the experience and qualifications to assist the trier of fact. See Snelson, 204Ill. 2d at 24; Zavala, 167 Ill. 2d at 546. The lack of an Illinois professional engineering license goesto the weight of Ramisch's testimony, not his competency. See Buford v. Chicago HousingAuthority, 131 Ill. App. 3d 235, 244 (1985) (allowing a witness to testify as an expert concerningelevator safety despite the witness's lack of knowledge or experience with elevator design,maintenance, repair, installation, applicable safety codes, union requirements respecting elevatormechanics, or day-to-day practices of elevator mechanics); see also Ralston v. Plogger, 132 Ill. App.3d 90, 98-99 (1985).

As we previously stated, in the interests of judicial economy and reaching an equitable result,a reviewing court may go beyond the certified questions and consider the appropriateness of the ordergiving rise to the appeal. P.J.'s Concrete Pumping Service, 345 Ill. App. 3d at 998-99, citing Bright,166 Ill. 2d at 208. Here, the order giving rise to the appeal arose from the trial court's decision togrant defendants' motion to strike the affidavit of Ramisch because he lacked an Illinois professionalengineering license. We must now reverse that decision, holding that the trial court abused itsdiscretion when it struck Ramisch's affidavit on the basis that he lacked an Illinois license.

In summary, we decline to answer the first certified question, and we answer the secondcertified question in the negative. Accordingly, the order of the circuit court of Lake County strikingRamisch's affidavit is reversed and the cause is remanded for further proceedings.

First certified question not answered; second certified question answered; order reversed andcause remanded.

BYRNE and GILLERAN JOHNSON, JJ., concur.