The purpose of this paper is to identify factors related to delinquency with accomplices, since offenses with accomplices are a characteristic of juvenile delinquency. The analysis employs data consisting of male delinquents who entered a juvenile classification home from 1986 to 1989. The information related to delinquents was collected from psychologists who took charge of diagnoses of the delinquents. Findings indicated that the factor of existence of accomplices was not attributed to belonging to deviant groups alone, although it was strongly related. In addition, the analysis found that delinquents isolated from peers were more likely to come from families whose guardians were less stable than were those having delinquent peers. The former tended to commit crimes by themselves, while the latter had a tendency to offend with accomplices.

As the consequence of the vulnerability of the self, defensive and compensatory structures of the self are built up in early childhood. These are the tendency to exhibitionism, grandiosity of the self, self-stimulation of body and narcissistic rage. Narcissism is the defense against the vulnarability of the self and the sense of shame. Kohut described narcissistic personality disorder in the case of the failure of the compensation of the vulnerability by the identification with the idealized self-object and narcissistic behavior disorder in the case of the failure of the defense of the vulnerability by exhibitionism and grandiosity of the self. Delinquency is the consequence of acting-out and is considered from the view of narcissistic behavior disorder. In oter words, it is not the consequence of over indulgement but the consequence of over vulnerability. For example, motorcycle gangs try to heal their vulnerability by their grandiose power, exhibitionism and self-stimulation gained by reckless driving. In the psychotherapy with delinquents, it is more important to provide them with mirroring-function than idealizing-function of self-object.

これまでさまざまな介入の研究を挙げてきたが，ここでもう一度まとめてみることにする．

(1) ここで検討した研究によると，個人的に介入処遇を行なうことは非行の予防には効果がないようである．

(2) ここで比較検討した家族への介入処遇についての研究間で，互いに矛盾する結果が出されている．しかし，家族全体に処遇し家庭内の相互関係パターンが改善されると，ある程度非行予防に効果がある可能性がある．

(3) 就学前の介入処遇は有効のようである．

(4) 学校への介入処遇では，研究結果に一致をみないが，教師だけでなく生徒にも介入処遇の影響を与えることができれば，ある程度有効と考えられる．

(5) コミュニティヘの介入処遇についてはまだ十分に研究されておらず，その効果の評価はできない．