Anti-social behaviours, sometimes called dissocial behaviours, are actions which are considered to violate the rights of or otherwise harm others by committing crime or nuisance, such as stealing and physical attack or noncriminal behaviours such as lying and manipulation. It is considered to be disruptive to others in society. This can be carried out in various ways, which includes, but is not limited to, intentional aggression, as well as covert and overt hostility. Anti-social behaviour also develops through social interaction within the family and community. It continuously affects a child's temperament, cognitive ability and their involvement with negative peers, dramatically affecting children's cooperative problem-solving skills. Many people also label behaviour which is deemed contrary to prevailing norms for social conduct as anti-social behaviour. However, researchers have stated that it is a difficult term to define, particularly in the United Kingdom where many acts fall into its category. The term is especially used in Irish English and British English.
Although the term is fairly new to the common lexicon, the word anti-social behaviour has been used for many years in the psychosocial world where it was defined as "unwanted behaviour as the result of personality disorder." For example, David Farrington, a British criminologist and forensic psychologist, stated that teenagers can exhibit anti-social behaviour by engaging in various amounts of wrongdoings such as stealing, vandalism, sexual promiscuity, excessive smoking, heavy drinking, confrontations with parents, and gambling. In children, conduct disorders could result from ineffective parenting. Anti-social behaviour is typically associated with other behavioural and developmental issues such as hyperactivity, depression, learning disabilities, and impulsivity. Alongside these issues one can be predisposed or more inclined to develop such behaviour due to one's genetics, neurobiological and environmental stressors in the prenatal stage of one's life, through the early childhood years.