The requirement that the cells be disrupted in order to extract the intracellular products has hampered the large-scale production of biotechnological products. Mechanical as well as nonmechanical methods are available for cell disruption, and the choice of a particular type of method depends both on the cell type and the products to be extracted. Among the cell disruption methods, French press and ultrasonication are the common methods used for laboratory purposes. High-pressure homogenizer is widely used in industries for cell disruption. Enzymatic and osmotic shock processes are also used for certain types of cell disruption. Heat generation, product degradation, and contamination from the disruptor are common problems encountered in cell disruption. Recently, modifications have been made to existing methods, and some of the methods are combined for better yield. Newly evolved techniques such as the use of a microfluidics platform in the disruption process has increased the overall efficiency. Chapter 1 reviews the important cell disruption techniques along with their merits and demerits. A brief description of micro-scale processes and single cell lysis techniques are also discussed in this chapter.