This letters journal, launched in 1986, consists of research papers covering current research developments in Particles and Fields, Gravitation, Cosmology, Astrophysics, Nuclear Physics, Accelerator Physics, and Quantum Information. A brief review section has also been initiated with the purpose of publishing short reports on the latest significant experimental findings and important new theoretical developments. Critical summaries and comments on a topic of current interest can also be considered as brief reviews, which preferably aim at non-experts. These reviews should examine the present state of the subject and attempt to provide future research in perspective.