With an estimated 2.5 billion online users, stress caused by cyber-interaction is becoming a significant and pervasive problem. In particular, phenomena such cyber-ostracism and cyber-bullying are sources of stress being reported with increasing frequency in modern cyber-connected workplaces (Wu, Yim, Kwan, & Zhang, 2012). In the present study, I sought to identify those factors such as emotional intelligence, which may explain individual susceptibly to cyber-ostracism, and in addition stress caused by difficult tasks. The conceptual model presented in this thesis, draws on William’s (2007) needs theory, and Baumeister and Leary’s (1995) social evaluative threat theory. To test the model, 232 undergraduate students completed the well-established, reliable and valid emotional intelligence Mayer-Salovey-Caruso- (MSCEIT, V2.0; Mayer, Salovey & Caruso 2002). Participants subsequently participated in a laboratory experiment designed to induce stress through difficult cognitive tasks and social exclusion. To achieve this, I developed a cyber-bullying scenario using fictitious virtual team members where participants were either included or ostracised. The level of stress experienced by the participants is determined by the change in the stress hormone salivary cortisol, from pre-intervention versus post-intervention. Those participants with low EI (as measured by the MSCEIT, Mayer & Salovey, 2002) are hypothesised to exhibit greater changes in cortisol, than the participants with high EI, particularly when engaging in easy tasks, or being ostracised. The results supported the hypothesis, that low EI participants engaging in easy tasks, and who experienced ostracism exhibited the greater change in cortisol than high EI participants. Further analyses demonstrate that the emotional management branch of the MSCEIT was the most significant predictor of stress moderation.