Abstract: Provided is a chemical mechanical polishing pad which as capable of draining used slurry from the polishing pad surface through the pad. Chemical mechanical polishing pads according to preferred embodiments of the present invention have slurry drain holes to drain slurry from the pad surface. In various preferred embodiments, the drain holes are combined with drain grooves in the pad surface and/or the pad/pad backing or pad/platen interface to provide a path for used slurry to exit the pad. The invention also provides a method of conducting CMP using through-pad slurry drainage.