We noticed considerable variation in anxiety among staff reporting blood exposure incidents and therefore undertook a study to investigate this. We studied 100 consecutive staff reporting blood or other body fluid exposures to the Occupational Health Unit. The nurse seeing the staff member administered a questionnaire about worries related to the incident, knowledge of HIV and hepatitis B transmission risks, perception of risk from the particular incident and predicted reaction of others that would be told. Level of anxiety was recorded on a visual analogue scale. Staff were then given information and counselling as usual, and asked to re-attend after a week, when the questionnaire was repeated. We found that the initial level of anxiety was not related to knowledge of HIV or hepatitis B transmission risks, but was related to perception of risk from the incident and to predicted reaction of others that would be told. The eight staff involved in exposures to known HIV-infected blood were not more anxious than the remainder. There was a reduction in anxiety between visits, which was significantly greater in women, in those who had a non-parental exposure and in those where the source patient was known. Knowledge of transmission risks also improved significantly between visits. This study underlines the importance of adequate counselling of staff who have suffered blood exposures.