Constantia Alexandrou received a BA degree with First Class Honors in Physics from the University of Oxford in 1980 and a PhD in Theoretical Strong Interactions Physics from the Massachusetts Institute of Technology, USA in 1985. She held research positions at the Paul Scherer Institute, Switzerland and at Erlangen University, Germany. She is a Professor at the Physics Department of the University of Cyprus, where she leads state-of-the-art research in Lattice Quantum Chromodynamics (QCD) and in studies of hadron structure. She is a member of the Extended Twisted Mass Collaboration (ETMC)  that included major European and US research groups in Lattice QCD. She heads the Lattice QCD Computational Lab. at the University of Cyprus, which operates clusters dedicated to Lattice QCD calculations. She has over 300 scientific publications and numerous invited talks at international meetings and has organized several workshops in Cyprus and abroad. She is a fellow of the American Physical Society.

She has served in numerous scientific advisory bodies and boards. Currently, she is the Chair of the Council of PRACE (Partnership of Advanced Computing in Europe), a   member of the National Council for Research, Technology and Innovation of Greece (ESETEK), a member of the Scientific Council of the John von Neumann Institute (NIC), a member of the Scientific Council of the Helmholtz-Institute Mainz  and the representative of Cyprus at IUPAP. She served as the first Head of the Department of Physics and she was Vice-Chair of the Interim Governing Board (IGB) of the Cyprus Institute from 2004 to 2007. She was the   Chair of IGB and Acting Director of the Computational-based Science and Technology Research Center of the Cyprus Institute from 2011 until 2022 securing about €15 million in competitive funding for its development, including two ERA Chair projects of €2.5 million each. 

She is the Principal Investigator of three European Joint Doctorates  of about €3.7 million each and the newly approved Excellence Center Quantum Computing for Science and Technology (QSciTec) under the Teaming action of  a total budget of €35 million.