Decentralized control is a promising method for large scale systems. A critical design method for decentralized control systems is desirable for solving the complicated design problem. Simple and explicit controller design becomes available with the idea of "function." However, the hierarchy based on the network structure may impose restrictions on controller design. At the same time, various kinds of exceptions such as faults, performance limits and so on may also impose restrictions. This paper proposes a method of the controller design under these restrictions. The concept of system connection is applied to derive the hierarchy. An exception is treated the same as a communication blackout. The hierarchy structure is intentionally manipulated to decide the priority order of the functions. The unified design for the system with the hierarchical structure and exceptions can be realized through this method.