Barium Isotopes are used in a wide variety of fields and applications. Ba-130 is used in the production of Ba-131/Cs-131 which is used in brachytherapy (seeds). Ba-132 can be used for the production of Ba-133 which is used as a gamma reference source. Ba-134 has been used to perform experiments in the field of nuclear physics. Ba-136 has been used to study photon scattering phenomena. Barium Isotopes Ba-136 and Ba-138 have been used in activation cross section experiments. Ba-135 has been used to validate the use of spinor symmetry while Ba-137 has been used in experiments regarding the theory of relativistic coupled clusters. Finally, Ba-138 has been used in studying r- and s- processes in stars.