Locusts and grasshoppers are among the most destructive agricultural pests. Their control is very critical for the food security worldwide and often requires governmental or international involvement. Even though locust and grasshopper outbreaks are now better controlled and are shorter in duration and reduced in extent, large outbreaks continue to occur in many parts of the world, sometimes promoted by climate change. Although some locust and grasshopper control systems are still curative, knowledge of the harm these plagues can cause and the socioeconomic effects of locust and grasshopper outbreaks have led to a growing paradigm shift from crop defence to preventive management. Effective preventive management strategy is based on improved pest biological and ecological knowledge and more effective monitoring and control techniques.