AbstractA distinction is made between acute and chronic stress in the workplace. The distinction leads on to two types of question: (1) How does the one relate to the other? (2) Is it possible to distinguish between acute and chronic stress physiologically? Preliminary attempts to tackle the latter question are reported. The subjects were anaesthetists on a cardiothoracic unit and the physiological measures taken were urinary cortisol and salivary flowrate. Perceived stress and arousal were monitored using self‐report techniques. Among the results obtained were the following:1Self‐reported arousal was higher in the morning than the afternoon.2The level of arousal was associated with salivary flow, flow being weaker when arousal was higher andvice versa.3Self‐reports of stress were associated with higher than average urinary cortisol levels.4The mean level of urinary cortisol over 24 hours was significantly higher for the group than that found in the general popul