Frustration is an emotion that occurs in situations where one is blocked from reaching a personal goal. The more important the goal, the greater the frustration. It is comparable to anger.

Sources of frustration may be internal or external. Internal sources of frustration involve personal deficiencies such as a lack of confidence or fear of social situations that prevent one from reaching a goal. Conflict can also be an internal source of frustration when one has competing goals that interfere with one another. External causes of frustration involve conditions outside the person such as a blocked road, lack of money, or lack of sexual activity.

In terms of psychology, passive-aggressive behavior is a method of dealing with frustration.

An increasingly common source of frustration is due strongly to the presence of computer technology. Because modern computing is marketed as user-friendly, it can be extremely frustating when one cannot achieve a goal due in part to a technological error, and because the user-friendly aspect is removed, many people find themselves unable to come to terms with their lack of options.