The hypothesis of charge‐transfer to the cuprate‐planes, which lies at the foundation for most theories on high‐temperature superconductivity, is re‐examined in light of recent neutron‐diffraction data for La2−&bgr;Sr&bgr;CuO4and Nd2−zCezCuO4. The data indicate that the cuprate‐planes do not acquire holes as the materials become superconducting, and that the superconductingp‐type regions of the unit cells are in the noncuprate‐plane charge‐reservoir layers instead. ©1995 American Institute of Physics.