Facing the flexible factors in the large project investing decision, the idea is put up that the large project investment should be decided flexibly in the direction of flexibility theory.

A lot of plans of investment on large projects aborted because of ignoring the risk.

Research on Symbiosis and Interaction between Large-scale Engineering and Ecosystem;

Large-scale engineering project has the characteristics of high investment,large scale,involving many factors and heavy effect.

The bearing capacity of water resources is affected by various factors, and the impact of large hydro projects is an important factor.

That extra large type project HX management is that the proprietor stimulates many agents who design, supervise managing, contracting business and so on, builds HX project process around "3+N " subjects.

The author systematically analysis the management characters of super-large engineering,and a project management information system Absorbing the latest information technology is developed and successfully used in Guangzhou West Tower project,so management process visualization,computer supported cooperative work,fine management,information sharing and decision supporting are realized.