Dr. Ionascu has taught at Philadelphia University, Houston Baptist University, Ursinus College, the University of Texas at Austin, University of Waterloo, and the University of New Hampshire. She has 27 years of experience teaching a variety of mathematics courses, including classes for math majors, such as calculus, linear algebra, real analysis, complex variables, and discrete mathematics; as well as classes supporting the liberal arts, including math for critical thinking, finite mathematics, and college algebra. She is doing research in operator theory, with a focus on reflexive operators, and she has presented her findings in scholarly articles and numerous presentations in Canada, Romania, and the U.S.

Dr. Ionascu has performed extensive professional service, including assisting Philadelphia University with obtaining accreditation for two engineering programs, organizing and providing tutoring, participating in various educational committees, assisting a local high school in math training for their junior level students, and serving as a referee for three mathematics journals.