Abstract: There are seven areas in social network research. First， how field forces or interference factors in the collective social network structure influence relations； second， how relations influence individual actions； third， how field forces or interference factors in the collective social network structure influence individuals' structural positions， fourth， how individuals' structural positions influence their individual actions； fifth， how individual actions influence the collective social network structure， sixth， how the collective social network influences collective actions， and seventh， how collective actions influence field forces. This paper takes the organizational theory and management research as examples to illustrate the research contents in each area and explains how social network serves as a bridge to connect collective actions and individual actions. The phenomenon of selforganization refutes the notion of collective actions equaling to a linear sum of individual actions； it manifests features of a complex phenomenondifferent selforganizations will lead to action ramifications and identical individual actions may result in opposing collective actions in different structures. To solve this nonlinear riddle is the important task in future social network research.

Key words: collective actions, field forces, individual actions, social network structure, social network theory