Survivalism is a social movement of individuals or groups (called survivalists or preppers) who proactively prepare for emergencies, such as natural disasters, as well as other disasters causing disruption to social order (that is, civil disorder) caused by political or economic crises. Preparations may anticipate short-term scenarios or long-term, on scales ranging from personal adversity, to local disruption of services, to international or global catastrophe. There is no bright line dividing general emergency preparedness from prepping in the form of survivalism (these concepts are a spectrum), but a qualitative distinction is often recognized whereby preppers/survivalists prepare especially extensively because they have higher estimations of the risk (odds) of catastrophes happening. Nonetheless, prepping can be as limited as preparing for a personal emergency (such as a job loss, storm damage to one's home, or getting lost in wooded terrain), or it can be as extensive as a personal identity or collective identity with a devoted lifestyle.

Survivalism emphasises self-reliance, stockpiling supplies, and gaining survival knowledge and skills. The stockpiling of supplies is itself a wide spectrum, from survival kits (ready bags, bug-out bags) to entire bunkers in extreme cases.

Survivalists often acquire first aid and emergency medical/paramedic training, self-defense training (martial arts, firearm safety), and self-sufficiency training, and they often build structures such as survival retreats or underground shelters that may help them survive a catastrophic failure of society.

Use of the term survivalist dates from the early 1980s.