As internet shopping matures, it is becoming increasingly important to study complaint intention and behavior. This study looks at two types of predictor: individual traits, such as self-confidence, attitude towards making complaints and prior experience of complaining, and situational factors, such as product importance, intensity of dissatisfaction, attribution of blame, and expectations. The subjects of this study were internet shoppers and the research was carried out by on-line questionnaire. The findings show that the higher the level of self-confidence, the more positive the attitude toward complaining. A positive correlation was found between previous experience of making complaints and the likelihood of making further complaints both in private to friends and family, and to the business that provided the product or service. Higher levels of self-confidence and perceived product importance also led to a greater likelihood of making a complaint to a third party.