conduct problems, the clinician often must rely on additional informants. However, infor-
mants’ knowledge of the individual’s conduct problems may be limited if they have inad-
equately supervised the individual or the individual has concealed symptom behaviors.
Individuals with conduct disorder often initiate aggressive behavior and react aggres-
sively to others. They may display bullying, th reatening, or intimidating behavior (includ-
ing bullying via messaging on Web-based social  media) (Criterion A1); initiate frequent
physical fights (Criteri on A2); use a weapon that can caus e serious physical harm (e.g., a bat,
brick, broken bottle, knife, gun) (Criterion A3);  be physically cruel to people (Criterion A4)
or animals (Criterion A5); steal while confronting a victim (e.g., mugging, purse snatching,
extortion, armed robbery) (Criterion A6); or force someone into sexual activity (Criterion A7).
Physical violence may take the form of rape, assault, or, in rare cases, homicide. Deliberate
destruction of others’ property may include delibe rate fire setting with the intention of caus-
ing serious damage (Criterion A8) or deliberate destroying of  other people’s property in
other ways (e.g., smashing car windows, vandal izing school property) (C riterion A9). Acts of
deceitfulness or theft may include breaking into someone else’s house, building, or car (Crite-
rion A10); frequently lying or breaking promises  to obtain goods or favors or to avoid debts
or obligations (e.g., “conning” other individual s) (Criterion A11); or stealing items of non-
trivial value without confronting the victim (e.g.,  shoplifting, forgery, fraud) (Criterion A12).