In terms of aggressive behaviours, one could imagine a continuum between Active Aggression (which includes violence & brutality) and Passive Aggression. Passive-aggressive behaviour refers to passive, sometimes obstructionist resistance to authoritative instructions in interpersonal or occupational situations. Sometimes a method of dealing with stress or frustration, it results in the person attacking other people in subtle, indirect, and seemingly passive ways. It can manifest itself as resentment, stubbornness, procrastination, sullenness, or intentional failure at doing requested tasks. For example, someone who is passive-aggressive might take so long to get ready for a party they do not wish to attend, that the party is nearly over by the time they arrive.

Someone who engages in passive-aggresive behavior typically won't confront others directly about problems, but instead will attempt to undermine their confidence or their success through comments and actions which, if challenged, can be explained away innocently so as not to place blame on the passive-aggressive person.

In some instances, the passive-aggressive may solicit the confidence of others as to their ability to perform duties, and then purposely sabotage those duties through procrastination or mishandling responsibility. Subsequent demands for performance are laid aside with claims of interference by the demanding parties or some other condition outside the control of the influence of the person who is engaging in passive-aggression, when in fact the delays and poor performance are due to the person's internal perception that to perform the task at another's demand is a demeaning insult to them. The omission of performance leaves the person in control of the situation, and allows that person to continue the aggressive behavior toward others. In cases where passive-aggression behaviors may indicate a personality disorder, these behaviours can persist even if it means personal loss to the passive-aggressive person, i.e. job loss or loss of esteem by others.

Some passive-aggressive behaviour may result from society's conditioning of individuals; direct confrontation can lead to harmful consequences. For example, confronting one's manager may lead to the loss of opportunities, such as being passed over for a promotion or even losing one's job. Not all passive-agressive behavior is problematic or a sign of a disorder.

Often passive-aggressive behavior manifests itself in individuals who view themselves as "peaceful." These individuals feel that expressing their anger through passive-aggressive behaviour is morally favorable to direct confrontation. Indeed, there are many cases where passive-agressive behavior may be more effective than direct confrontation, so many times individuals who are engaging in passive-aggresive behavior are acting rationally.

Passive-aggressive personality disorder is a controversial personality disorder proposal, said to be marked by a pervasive pattern of negative attitudes and passive resistance in interpersonal or occupational situations.

A passive-aggressive may not have all of these behaviours, and may have other non-passive-aggressive traits.

• Ambiguity

• Avoiding responsibility by claiming forgetfulness
• Blaming others & not taking responsibility
• Chronic lateness and forgetfulness
• Complaining
• Does not express hostility or anger openly
• Fear of competition
• Fear of dependency
• Fear of intimacy
• Fears authority
• Fosters chaos
• Intentional inefficiency
• Making excuses and lying
• Obstructionism
• Not returning email or telephone messages
• Avoiding eye contact
• Using BCC: on email messages
• Procrastination
• Resentment
• Resists suggestions from others
• Sarcasm
• Sullenness

"Merely being passive-aggressive isn't a disorder but a behaviour — sometimes a perfectly rational behavior, which lets you dodge unpleasant chores while avoiding confrontation. It's only pathological if it's a habitual, crippling response reflecting a pervasively pessimistic attitude". Cecil Adams

When the behavior is part of a disorder, the lack of repercussions resulting from passive-aggressive behaviour can lead to an unchecked continual attack, albeit passive, on one's acquaintances. The treatment of this disorder can be difficult, mostly because efforts to convince the person that they have this problem are met with resistance, and the passive-aggressive will frequently leave a treatment regimen claiming that it did no good. Since the effectiveness of various therapies have yet to be proven, these individuals may be correct.

In the psychoanalytic theory of transactional analysis, many types of passive-aggressive behavior are interpreted as "games" with a hidden psychological payoff, and are classified into stereotypical scenarios with names like "See What You Made Me Do" and "Look How Hard I've Tried".

Compiled using DSMIV and Wikipedia