OBJECTIVETo study the basic law of circulation of channels and collaterals.

METHODSInherit and develop ripe experiences of predecessors based on The Yellow Emperor's Internal Classic and other classic medical books.

CONCLUSIONCirculation of channels and collaterals has the eight laws, including naming law, distribution law, converging law, exterior-interior association law, beginning-ending running law, meridian-qi bidirectional circulation law, zang- and fu-organ pathway liaison law, and liaison law of connecting with trunks and sense organs.