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Our Solar System has kept a record of the earliest phases of its evolution, at the time when all current ingredients were dispersed in a dense molecular cloud, the pre-stellar cloud core. This is testified by the similarities between the chemical composition of primitive material, such as comets and carbonaceous chondrites, and that of young protostars, where the pre-stellar ices have just evaporated. Of particular interest are the D and 15N fractionation processes in H- and N-bearing molecules present at the various phases of star- and planet-formation, as they provide information on the chemical journey from clouds to planets, thus our astrochemical origins. Here, I will summarize our current understanding of D- and 15N-fractionation in molecular material from clouds to protoplanetary disks and highlight puzzles.