The present study aimed to assess regional variations in the pattern of pre-imprisonment drug use and its correlates among female inmates. A consecutive sample of 3389 admissions to Scotland’s only exclusively female prison were assessed as to their pre-imprisonment drug use in the six-months period prior to custody. Type of drug, method of administration, offence type, pre-imprisonment area of residence, HIV and hepatitis status, and history of drugwithdrawal related epileptic seizures were recorded. A sample of 709 inmates reported a history of drug use in the six months prior to imprisonment. Full data were available for a subsample of 616 subjects who indicated a level of drug dependence. Marked regional variations occurred in that a significantly larger proportion of drug users (88.7%) in comparison with non-drug users (53.5%) were resident in Glasgow prior to incarceration. Drug users from Glasgow, in comparison with drug users from other areas of Scotland, were significantly more likely to have used heroin and temazepam, less likely to have used dihydrocodeine, lar less likely to have used methadone, and more likely to have been imprisoned for prostitution. Individuals who had used heroin and temazepam especially were more likely to have experienced drug-induced epileptic seizures. Results are discussed in relation to the possible precipitating factors associated with regional variations.