A corporate activities business-cycle model composed of PLAN, DO, and SEE activities is described. This model is constructed on two layers: an organizational layer and an individual layer. Regularity of both data structures and algorithms is defined from program production aspects as follows: if the data structures and algorithms of a program can be defined prior to all computations, they are regular, otherwise they are irregular. It is shown that unique information technologies are required to develop each system. Several information technologies are proposed for each information system: real-time database maintenance for DO information systems, a data supply system for SEE information systems, an automatic index generator and a virtual office environment for PLAN information systems, and private data management and automatic terminal operation for PLAN and SEE information systems at an individual layer under organizational DO activities. >