This book is intended for student, practitioners and managers of various production unit process to ensure effective control of key parameters that relate to efficiencies of process. It contains the basic theory underlining efficiency and its relationship with the key control parameters. The assessments apply sampling, statistical and metallurgical principles to enhance managerial decision in operating unit process. Alternatively, this book provide a new principle for managing efficiency within a predictable concept. Notably, this book bring into focus the principles of using multi-stage cluster sampling technique and trendlines to evaluate dependable control parameter that can be used to monitor efficiency.