A multi-level cell (MLC) one-selector-one-resistor (1S1R) three-dimensional (3D) cross-point memory system includes at least one MLC 1S1R structure including a stacked arrangement of a phase change memory (PCM) cell and a threshold switch selector. An electrically conductive bit line is in electrical communication with the OTS selector, and an electrically conductive word line is in electrical communication with the PCM cell. A controller is in electrical communication with the bit line and the word line. The controller is configured to select at least one voltage pulse from a group of different voltage pulses comprising a read pulse, a partial set pulse, a set pulse, a partial reset pulse, and a reset pulse, and configured to deliver the selected at least one voltage pulse to the at least one MLC 1S1R structure.