This is an introductory course to the concept of multi-hazard early warning in coastal areas. It will consider the range of hazards that threaten communities living in coastal areas, including both rapid and slow onset hazards. It will examine the role of early warning in preventing loss of life and minimising economic losses, including multi-hazard early warning systems that address several hazards and/or impacts of similar or different type in contexts where hazardous events may occur alone, simultaneously, cascadingly or cumulatively over time, and taking into account the potential interrelated effects.