クラウドコンピューティングやNGNの進展，広域イーサネットや無線LANサービスの普及等に見られるようにネットワークサービスの多様化が進んでいる．すなわち，いつでもどこでも容易にネットワークが利用できるユビキタス環境が一般化してきている．個人のワークスタイルも，これまでの時間や場所の枠を越えた形態が可能になっている．一方，今後の少子高齢化社会，ライフスタイルの多様化等を視野に入れた場合，個人の活動も企業内だけでなく，社会や地域との関わり合いが重要となる．本論文では，このような背景をふまえ，新たにネットワークと情報システムを連携させたサービスとして個人の活動を情報システムで支援するサービスを提案するものである．すなわち，個人が所属する企業での活動や社会・地域における活動を情報システム上のグループ活動としてとらえ，これらを支援するサービスの提案を行う．具体的には，個人の活動をそのコンテキスト情報であるTPO条件（Time：時間，Place：場所，Occasion：状況）に応じて支援する動的多重帰属グループサービスを提案し，サービス実現のための要件定義，アーキテクチャを示した．本サービスの実現においては，個人と複数の組織との関係を自動的に管理するグループ間競合制御機能がキー技術であり，新たにハイブリッド制御方式を提案した．これらに関して，プロトタイプシステムを開発し，提案サービスの有効性を明らかにした．

The diversification of the network service has been proceeding so that it may be seen in the development of cloud computing and NGN, the diffusion of wide area Ethernet and the wireless LAN service, and so on. That is, the ubiquitous environment where a network can be used always anywhere easily is becoming common. As for the individual work style, business in the ubiquitous environment has been getting possible in the same way. On the other hand, when a future aging society with fewer children and the diversification of the lifestyle are put into a view, it is thought that being related with not only the inside of a company but society or an area becomes important also for the individual activity. In this paper, “service which supports the individual activity with an information system” is proposed as service which made the network and the information system newly cooperate based on such a background. That is, activity in the company to which an individual belongs, and the activity in society and the area are regarded as group activity on an information system, and the service which supports these is proposed. The dynamic multi-homing group service which specifically supports the individual activity according to the TPO conditions which are the context information was proposed, and the requirement definition for service realization and architecture were shown. In realization of this service, the contention control function between groups to manage automatically the relation between an individual and two or more organizations is key technology, and the hybrid control system was newly proposed. About these, the prototype system was developed and effectiveness of proposal service was clarified.