  A critical review of the standard paradigm for the origin of Galactic cosmic
rays is presented. Recent measurements of local and far-away cosmic rays reveal
unexpected behaviours, which challenge the commonly accepted scenario. These
recent findings are discussed, together with long-standing open issues. Despite
the progress made thanks to ever-improving observational techniques and
theoretical investigations, at present our understanding of the origin and of
the behaviour of cosmic rays remains incomplete. We believe it is still unclear
whether a modification of the standard paradigm, or rather a radical change of
the paradigm itself is needed in order to interpret all the available data on
cosmic rays within a self-consistent scenario.
