This workshop focuses on the next milestone in cosmic-ray physics, that is the detection of antideuteron or antihelium nuclei by the present or next generation of space instruments: a challenging but promising avenue in the search for new physics. The goal of this workshop is to bring together scientists from different fields, from astroparticle to nuclear physics, to discuss about the experimental challenges and the theoretical implications of the detection of antinuclei in Galactic cosmic radiation.