ABSTRACT
The original techniques of statistical quality control (SQC) have been available for over three-quarters of a century; Shewhart’s first book on control charts was written in 1924. There is now a vast academic literature on SPC and related subjects such as six-sigma. However, research work carried out by the author and his colleagues in the European Centre for Business Excellence, the Research and Education Division of Oakland Consulting plc, has show that managers still do not understand variation.
