Cuprate-planes are not necessary and essential for high-temperature superconductivity: doped Sr 2 YRuO 6 superconducts fully at 23 K in its SrO layers once the Ru stops librating (the material begins superconducting at ≈ 49K). GdSr 2 Cu 2 RuO 8 superconducts near 45 K in its SrO layers, not in its cuprate-planes. By examining the charge transfer, we find that Tc increases with the number of layers n and with pressure p in the HgBa 2 Ca n-1 Cu n O 2n+2 compounds, as does the charge in the BaO layers (and not the charge in the cuprate-planes), indicating that the superconductivity is in the BaO layers. Four superconductors, including PrBa 2 Cu 3 O 7, were successfully predicted to superconduct not in their cuprate-planes, but in their BaO or SrO layers. The original claims that the superconductivity resides primarily in the cuprate-planes are invalid.