In a comparative study of ageing techniques on 101 Roe deer from Hamsterley Forest, County Durham, it was found that cementum layering in the incisor was completely reliable and that in the molar slightly less so. Estimates of age from cusp wear and general attrition of the dentition were highly correlated with those from layering. The rate of tooth wear was high. The dry weight of the eye lens was of little value as an index of age. The annual static mortality of both sexes was apparently close to 30% throughout most of the life span, and the form of the life table similar to that of female Roe deer in Thetford Chase, East Anglia, and on the Kala estate in Denmark. The oldest individuals obtained were aged 9½ years.