Process improvement through cellular manufacturing, engineering, and management (CEM) is largely dated and neglected. This article aims at rejuvenating the topic through re-conceptualization in the form of twelve principles of workcell design, operation, and management, plus six corollary principles. An assessment model, based on the twelve principles is suggested for planning and evaluating proposed or operational CEM cases. Much of the attendant research emerges from published case studies, along with authors’ own extensive, on-site visitations and analyses. Collectively, an intent to present rationale for considering and treating the workcell/cellular construct as among the more significant concepts/methodologies within the field of manufacturing/engineering/production management.