"The flavour structure of matter remains one of the deepest challenges to our current understanding of the elementary particles and their interactions. Indeed, even after more than half century of intense research the flavour patterns underlying most of the high-energy physics processes defies our comprehension. The Standard Model of particle physics, the best description of the sub-nuclear world ever conceived, does not provide any clues to why we observe just three families of quarks and leptons, what is the origin of the peculiar pattern of their quantum-mechanical mixing or why their masses range over more than twelve orders of magnitude. With the advent of the next generation of particle physics experiments, in particular the Large Hadron Collider, the high-precision neutrino facilities, large-volume rare decay searches and other kinds of instruments and techniques focusing on uncovering physics beyond the Standard Model, there is a growing and well-founded expectation that the next decade could witness the first glimpse on these mysteries. The current proposal addresses these fundamental problems from the perspective of Grand Unification, one of the best motivated hypotheses about the nature of the fundamental dynamics governing the very birth of the Universe. A thorough understanding of the elusive low-energy imprints of physics at very high energies provides a unique strategy for testing the unification paradigm, complementing the traditional techniques of its experimental scrutiny. Apart from unwinding further the conundrum of the perennial problem of flavour, the proposed programme stresses the interdisciplinarity, covering topics from astroparticle physics and cosmology up to the experimental signatures and collider phenomenology. In this respect, it has a very strong potential to extend significantly the fellow's research profile, bringing him to the level of a full professional maturity."