Abstract: Graphical editing methods are employed to construct programs in high-level graphical languages prior to compilation and operation in controllers for industrial or commercial equipment. The editing methods include process, hardware and program editing tasks for defining both process and hardware I/O points and connecting them to variables in a controller program. Each editing task has a tree graph window, a graph editing window, and a palette with rotating panels of graphical editing tools. The hardware editing taks uses two-layered icons to graphically simulate the hardware environment. A plurality of graph types are based on generalized node-vert-arc graphical elements which are special classes programmed in the Smalltalk programming language. Languages for the controller program include function block, sequential function chart and ladder diagram.