In this field study self-confidence was tested to predict the course of galvanic electrodermal stress response prior, during and after public speaking. Ten graduate students initially rated their self-confidence and afterwards presented their thesis proposals orally in a 10-min presentation to their supervisor and peers. Galvanic skin response level was measured throughout and analysed for 10min prior to, during, and 10min after the presentation. Two major galvanic electrodermal stress response types were observed. Five students showed a ‘healthy response', i.e. an anticipatory increase in electrodermal conductance, followed by a decrease after termination of the presentation. The other five students showed a steady increase of skin conductance during and after their presentation (‘prolonged response'). In line with the allostatic load model the ‘prolonged response' group reported significantly lower self-confidence before presentation than the ‘healthy response' group (p<0.01). Self-confidence is a resource in novices facing an unfamiliar stresso