We present the results on structure, superconductingTc,and magnetic ordering temperature of Pr moments of several Pr substituted rare earth (RE) oxide systems such asY1−xPrxBaSrCu3O7(Y/PrBaSr:123),La1−xPrxBaCaCu3O7(La/PrBaCa:123) andNd1−xPrxBaCaCu3O7(Nd/PrBaCa:123). We observe that the suppression of superconductivity due to Pr in all these systems is less in comparison to that in their RE:123 counterparts, i.e., in Pr substituted Y:123, La:123 and Nd:123, respectively. Interestingly with full Pr substitution in RE:123 compounds, the Pr moments order antiferromagnetically at 17K, while in the presently studied three systems, the same happens at around 10K only. Antiferromagnetic ordering temperature of the Pr moments of the end member of the series, which may be taken to be a measure of the strength of the hybridization of Pr-4f orbitals with Cu-O conduction band, appears to have a direct correlation with suppression of superconductivity in the corresponding series. Our results suggest that by various on-site substitutions or by modifying the parent unit cell of Pr:123 compound, one may be able to isolate the Pr-4f magnetic moments or decrease their interaction with the Cu-O conduction band, and achieve superconductivity in the presence of Pr. ©1999 American Institute of Physics.