Physical Self Defense is the use of physical force to counter an immediate threat of violence. Such force can be either armed or unarmed. In either case, the chances of success depend on a large number of parameters, related to the severity of the threat on one hand, but also on the mental and physical preparedness of the defender.

Many styles of martial arts are practiced for self-defense or include self-defense techniques. Some styles train primarily for self-defense, while other martial/Combat sports can be effectively applied for self-defense. To provide more practical self-defense, many modern day martial arts schools now use a combination of martial arts styles and techniques, and will often customize self-defence training to suit the participants' lifestyles, occupations, age groups and gender, and physical and mental capabilities.

The best Unarmed Defense Techniques (UDT) are often a handful of simple gross motor skills that are used to 'bash and dash' rather than highly complex fine motor skills that deteriorate under stress. Learning UDT is about increasing confidence and awareness not about 'beating' an attacker. Good UDT lessons will teach simple, high impact techniques to momentarily distract or off-balance an attacker so a victim can get away.