The article describes the usefulness of introducing redundancy into accounting messages. It has also suggested two systems for developing redundancy. These are the use of multiple income reporting including a concept of price changes and a reporting system of historical cost income with physical and environmental information added. The last section discusses their cost and value problems. This cost and value approach has, admittedly, a number of limitations. Some of the variables and the constants in the above formulas have no means of evaluation at present, the annual social loss from continuing the historical cost system. Also, there might be some variables left out of consideration, and even as to those taken into account the above functions may not be true reflections of the realities. Because of these limitations this study would be conceptual, illustrative and introductory rather than operational, all-inclusive and final. Finally, the multiple reporting system and the physical and environmental information system are not incompatible. For example, an accounting system would be conceivable which contains at the same time redundancy in the form of explicit real income and also that physical and environmental information which would aid in the prediction of future economic resources of the firm.