Psychiatric consultants to city and county jails are confronted with the challenge of preventing jailhouse suicides, a problem of national scope. Suicide prevention programs in jails must emphasize screening and identification, psychological support, observation, disarmament, clarity and consistency, and diagnosis, treatment, and/or hospitalization. Exactly how these principles are formulated and implemented will depend on the unique circumstances of each jail. Finally information is presented as evidence that a program that embodies these principles can effectively reduce the number of suicides in a jail where the average daily census has increased from fewer than 400 to greater than 900 in the past six years.