IPC-9191 reflects the principals of statistical process control (SPC) represented by ISO-DIS 11462-1, Guidelines for Implementation of Statistical Process Control (SPC) - Part 1: Elements of SPC. This document outlines the SPC philosophy, implementation strategies, tools, and techniques used for relating process control and capability to final product requirements. 43 pages. Released November 1999. Supersedes IPC-PC-90.