In this paper MATT, a Groupware Calendar System (GCS), is presented. The MATT system provides users with a shared calendar service by preserving the right to the privacy and also by presenting features for arranging meetings automatically. The core of the proposed GCS system is a Multiagent infrastructure which manages the shared calendar and drives the process of arranging meeting in an effective way. An advanced network management system allows MATT working regardless the connection is present or not.