Material and energy (M&E) balances are fundamental to chemical (process) engineering, environmental engineering and industrial chemistry. This text presents M&E balance calculations in a compact, transparent format accessible to students and professionals in the above fields, and to others who want to quantify the physical progress of our civilization.The text embraces all topics covered in corresponding engineering undergraduate courses and deals with environmental and sustainability issues of current concern to society. The general balance equation is the foundation for a review of relevant science and economics, and hence, for material and energy accounting in batch and continuous chemical processes. The text focuses on SI units, using flowsheets and stream tables in computer spreadsheets to represent practical systems. Worked examples range from simple stoichiometry to modeling multi-unit recycle and unsteady-state processes.