Geographic information systems have emerged as a hot property in the past year, and in the latest development, Infodata Systems Inc, Rochester, New York has reached agreement in principle to acquire Synectics Corp, a Fairfax, Virginia professional services firm specialising in advanced simulation and modelling, digital cartographic mapping, terrain assessment, database evaluation and systems integration, and offers its services primarily to the US government; Infodata looks for completion in 60 days, but terms were not disclosed.