T his virtual special issue (VSI) of Industrial & Engineering Chemistry Research (IECR) is a collection of contributions that were presented at the fourth North American Symposium on Chemical Reaction Engineering (NASCRE-4) in Houston, Texas, in March 2019. Chemical reaction engineering is central to the success of the chemical industry, energy production, clean transportation, and environmental technology and will continue to play a vital role in future economic growth. This symposium underscored the important role of Chemical Reaction Engineering (CRE) in that success. The theme of NASCRE-4 was "Making Boundaries Malleable: Advancing Reaction Engineering through New Materials, Unique Chemistries and Advanced Computation", which offered a broad topic that allowed the meeting to incorporate the most cutting-edge research in the core of the discipline while welcoming exciting advances in the emerging areas in the field.The meeting brought together leading scientists from various fields to share the latest research on some of the most challenging problems pertinent to the theory and practice of CRE. The program was comprised of two plenary lectures, two award addresses, 10 keynote talks, 78 regular oral presentations, and 40 poster presentations and engaged over 210 registrants from around the world with a healthy mix of researchers from academia, industry, and government. The excellent participation from the next generation of chemical reaction engineers was a particularly exciting aspect of the meeting and is reflected in the contributions to this special issue.