Spin physics in high-energy hardon interaction

Data on single-spin asymmetry (A_N) in high-energy hadron-hadron collisions are discussed. The data are classified according to the beamand target types. The single-spin asymmetry A_N is considered as a function of kinematical variables and the sort of participant particles. Data from the PROZA and FODS facilities operating in beams of the IHEP accelerator are presented. The origin of a large single-spin asymmetry is briefly considered.