Distributed GIS is a complicated software system. Applying Agent technology into distributed GIS will provide a new concept and method to construct distributed GIS system and applications. In this paper

modeling distributed GIS

searching and retrieving spatial information on Internet

constructing service framework for WebGIS

building spatial decision-support system and interoperating in GIS are introduced.Firstly

an agent-based distributed GIS model named as Geo-Agents is studied

which consists of four types of GIS agent: Facilitator

general agent

GIS functional agent and GUServer. All of these agents cooperate to complete GIS tasks.Combining agent technology and spatial metadata to locate and retrieve spatial information is an effective method to process distributed spatial information. A hierarchical spatial metadata database framework is designed to manage spatial databases

layers and maps on network. With the help of spatial metadata

five agents are constructed to distribute on network

search

locate

retrieve and filter distributed spatial information initiatively and cooperatively.Then

an agent-based common WebGIS service framework is introduced

which is divided into three layers: user layer

application layer and service layer. It can provide GIS services for different applications and different groups of users at the same time.Also

an agent-based intelligent spatial decision-supporting system is presented

which is a federal system consisting of many agents. All of these agents cooperate to complete spatial decision-supporting tasks.Finally

an agent-oriented GIS interoperating specification is explored

which has common spatial data interface

common GIS agent descriptive specification and common agent communication mode.