Weak interactions in nuclei, with beta decays and muon capture reactions in particular, have been used, over the last forty years, as the unique laboratory for studying fundamental symmetries. Upon surveying briefly my past research efforts in relation to the hypothesis of conserved vector currents (CVC), partially conserved axial currents (PCAC), and the absence of second-class currents, I wish to identify some unique roles that weak interactions in nuclei are yet to play as we venture into the twenty-first century.