Three groups of factors which might affect the blood biochemistry of red deer (Cervus elaphus) were examined. These were the wounding site (head/neck versus chest), the stalker who collected the blood (coupled with the geographical area where each deer was shot), and the sex and nutritional status of the deer. The activities of muscle enzymes, creatine kinase, aspartate amino transferase, and lactate dehydrogenase, were markedly higher in the plasma of deer shot in the chest as compared with those shot in the head or neck; the plasma also looked different, being deep cherry red in colour in the chest-shot deer. Other biochemical measures were unaffected by the wounding site. Blood collected by one stalker from the chest cavity had higher activity of the liver enzyme, glutamate dehydrogenase, higher concentration of potassium and lower concentrations of sodium and chloride than blood collected by another stalker from a knife wound in the base of the neck. Otherwise the method of collecting blood had very little effect on blood biochemistry. Cortisol was unaffected by the wound site nor, probably, by the method of collecting blood, but was highest in the stags living in a more mountainous region and in those deer that had to be shot twice before they died. Stags, which were shot in the rutting season and were probably fasting, had significantly higher concentrations of free fatty acids than hinds. Lactating hinds had significantly less fat on their kidneys than non-lactating hinds and stags. All hinds, which were shot in winter, had lower concentrations of urea than stags, which were shot in the autumn.