Аннотация:According to the body function regulation model approach to identity, we suggest to differentiate at least five different variants of identity formation: emotional commitment, simple identification, concealed identification, identity fusion, cognitive and affective processing. They reflect different forms of subjective control underlying the feelings of belonging or possessing regarding social groups. Our empirical study concentrates on the structural and functional differentiation of two variants – identification and identity fusion regarding four social groups (family, friends, country and organization) in two samples of adults (N1=282 and N2=100). The methods include the Russian versions of the Identity Fusion and Identification Scales, the Utrecht-Management of Identity Commitments Scale, the Subjective Happiness Scale, the Satisfaction with Life Scale, the Positive and Negative Feelings Scale as well as the modification of the “Who am I” method with the quantitative appraisal of valence, salience and the social approval of identifications. According to the results, factor analysis supports the structural differences between identity fusion and identification for all four social objects with almost no gender and age effects. For all four groups, identification and identity fusion are independent predictors of identity commitment and in-depth exploration as well as negative feelings about possible identity change. For the large groups, such as country and organizations, they independently relate to a lower reconsideration of commitment. While for the small groups (like family and friends), the reconsideration is associated with fusion only. The data also suggest that the emotional component of well-being is closer related to identity fusion (happiness, positive, negative emotions).