The 20th International Conference on Systems Engineering Research (CSER 2023) pushes the boundaries of systems engineering research and responds to new challenges for systems engineering. CSER 2023 invited researchers and practitioners to submit their work in alignment with the thematic focus on a smart and sustainable world. CSER was founded in 2003 by Stevens Institute of Technology and the University of Southern California, and in 2023 the conference returned to the Stevens campus in Hoboken, New Jersey.