This study seeks to investigate the relationship between indices of shyness, physiological reactivity and gender. A sample of twenty college students (10 females; 10 males) were presented with a series of computer based memory tasks. Simultaneously, physiological activity (including blood pressure and heart rate) was monitored. Participants were then given two questionnaires, McManus et aI's (1997) updated version of the Norton Communication Style Measure (CSM) Questionnaire, and Rosenberg's (1989) Self Esteem Questionnaire. Results indicate that: (a) Sex difference in self esteem exists (i.e.) males reported higher levels of self esteem than females, and (b) self reported non verbal communicative style was associated with lower levels of cardiovascular reactivity. It may be inferred from these results that non verbal communicative style may reduce the risk of coronary heart disease by its action on reducing systolic blood pressure.