Abstract: This paper proposes the concepts of topen-loop decision system (OLDS) and close-loop decision system (CLDS),primarily discusses decision support theory (DST) and adaptive decision support,then outlines the research frameworks of decision support system engineering (DSSE) and decision support system integration (DSSI). This paper pointed out that the majority of researches have focused on OLDS,which is necessary to study decisionmaking and decision support, but not enough. If we want to enhance the effectiveness of decisionmaking and decision support, we should research into CLDS,study decision problem recognization and solving in the unified framework of decision system.

Key words: decision support system, decision problem recognizing, decision problen solving