The experimental observations of exotic hadron candidates in various processes during the past years have triggered tremendous theoretical efforts on the understanding of their structures. In this talk I will stress some crucial issues concerning the production mechanisms and possible criteria for QCD exotics.

Qiang Zhao (Prof. Dr. of Physics) received his B.S., M.S. and Ph.D. from Peking University during 1988-1998. He worked as a postdoc in Institut de Physique Nucleaire (IPN-Orsay), France, during 1998-2000, and later as a postdoc and EPSRC Advanced Research Fellow in University of Surrey, UK. He joined IHEP as a full professor in 2005 working in the field of theoretical hadron physics and high-energy nuclear physics.  In 2014, he received the NSFC Outstanding Youth grant support,  and in 2019 he was awarded the  “ WU You-xun (WOO Yui-hsun) Prize ” of Chinese Physical Society.