The regulation of all components of the process flow is referred as control in the process industries. Hence, ensuring precise control is regarded as the primary objective of a control engineer. To successfully generate end goods, refining, mixing, handling, and manipulating fluids may necessitate precise, demanding, and possibly dangerous processes. To generate the required final product with minimal use of raw materials and energy is expected. This work involves modeling, developing control techniques and further applying these, in a CSTR (Continuously Stirred Tank Reactor). This book has three main segments, they are modelling an unstable CSTR, designing a suitable controller to stabilize the reactor and DCS implementation using DeltaV PredictPro.