Guglielmo Mastroserio is a Marie Curie Individual Fellow at the Università Statale di Milano.

He obtained his PhD in 2019 at the University of Amsterdam working with Prof. Michiel van der Klis on spectral-timing analysis of accreting black hole system. He continued his research as a Postoctoral researcher at Caltech in the NuSATR group under the supervision of Dr. Javier Garcia. Then he briefly joined the Istituto Nazionale di Astrofisica INAF in Cagliari for 1 year working with Dr. Matteo Bachetti.

He studies accreting black holes of all sizes, from stellar mass black holes to active galactic nuclei (supermassive black holes). He works on modelling the X-ray radiation emitted in the nearest proximity of black holes