Content and Objectives This text deals with the control of boilers. In the context of the coverage included@ the emphasis will be on high pressure (above 15 psi ) steam boilers as applied for power generation and process heat supply. Most of the included material will apply equality to electric utility boilers used for power generation and to smaller boilers for light industrial@ commercial@ and institutional heating applications. Boiler control is a broad subject that includes the total start-up and shutdown procedures@ as well as safety interlocks and the on-line operation of the boiler. The first edition of this text concentrated on the on-line aspects of boiler control. This edition includes coverage of start-up@ shutdown@ flame monitoring@ and safety interlock measures.