The state Association of Nurse Anesthetists brought an action against the Commissioner of Health, Department of Health, and the Public Health Council, claiming that the defendants' issuance of Clinical Guidelines for Office- based Surgery (promulgated to "ensure that the public is adequately protected when undergoing surgery/invasive procedures in private offices of health care practitioners"), were ultra vires, or outside the Commission's authority. The Guidelines effectively prohibited CRNAs from administering anesthesia for office-based surgery. The defendants' conceded that they had no authority to regulate services in private physician offices, but contended that the Guidelines were just suggestions, not regulations. The Appeals Court held that the Guidelines were, in fact, regulations promulgated with the intention of dictating the conduct of professionals conducting surgery in private offices, and that the Commission impermissibly acted in the absence of legislative guidance and contrary to an express legislative mandate prohibiting the defendants from promulgating rules or regulations concerning the professional misconduct of physicians.