Summary: In this paper, concentrating on the Hou Zhenting’s paper “The criterion for uniqueness of a \(Q\)-process”, we review a number of associated results of the existence and uniqueness for \(Q\)-processes, especially Hou-Conditions (\(H\)-conditions) at the construction of \(Q\)-processes. We successively summarize the existence and uniqueness for honest \(Q\)-processes, revisable \(Q\)-processes, stochastically monotone \(Q\)-processes, dual \(Q\)-processes and \(Q\)-processes in abstract space, give some associated results for birth-death processes, and point out three unsolved open problems. We wish to help Chinese young probability scholars to understand the outstanding contributions of Chinese probability seniors especially Mr. Hou.