In the early 1970s, when computing capabilities were tiny, tiny, tiny compared to even a cell phone today, and those resources were typically time-shared across multiple users, queueing network models became a primary tool to analyze and improve system performance. Queueing models had been studied for years before regarding communication systems and other systems, but networks of queues seemed especially apropos for understanding time-sharing systems. Computer Systems Performance Modeling, which Professor K.M. Chandy and I wrote in 1978-9, previously published by Pearson Education, Inc. is now out of print. We are making PDF copies of lightly edited versions available under a Creative Commons license. https://notes.technologists.com/notes/2020/08/25/computer-systems-performan… Ed MacNair and I published two books based on The Research Queueing Package, RESQ: Simulation of Computer Communication Systems and Elements of Practical Performance Modeling. Those books, previously published by Pearson Education, Inc. are now out of print. We are making PDF copies of lightly edited versions available under a Creative Commons license. Though we have written two prior articles about RESQ history, those did not cover subsequent development, so another recap seems appropriate now. https://notes.technologists.com/notes/2020/08/25/remembering-resq/ (Mainstream Videoconferencing: A Developer’s Guide to Distance Multimedia, which Joe Duran and I wrote from 1994-96, became available again in 2008: https://notes.technologists.com/notes/2008/02/14/mainstream-videoconferenci…) -- voice: +1.512.784.7526 e-mail: sauer(a)technologists.com fax: +1.512.346.5240 web: https://technologists.com/sauer/ Facebook/Google/Skype/Twitter: CharlesHSauer -- voice: +1.512.784.7526 e-mail: sauer(a)technologists.com fax: +1.512.346.5240 Web: https://technologists.com/sauer/ Facebook/Google/Skype/Twitter: CharlesHSauer