In this paper CAD performance in the field of simulation, testing, and layout is compared to the increase of digital integrated systems complexity. This complexity already exceeds the fundamental limits of existing software, especially in the testing area. On the other hand, fully manual layout of VLSI leads to unreasonably long design times and extremely high risks. This will favor design automation methods in layout. Testability and layout will most likely impose some sacrifice of VLSI overcapacity to a more structured system architecture. This architecture will lead to testable dedicated VLSI system design through the use of automated design software to keep development costs low. Copyright © 1979 by The Institute Of Electrical And Electronics Engineers, Inc.