YUGO's prison ministry in Tijuana began in August 2001. At that time, the La Mesa Prison housed men, women and children in deplorable conditions. Family members of inmates were allowed to stay in the prison and rent a tiny space for a house or business. Drugs, prostitution, pregnancy and disease were commonplace. In August 2002, the prison was completely changed, as all non-inmates were removed (including children, which left many orphaned), and "businesses" and "houses" were bulldozed. A year later, women inmates were separated from the men and given their own separate area in the prison. Drugs are not as accessible to the women as to the men and there is a sense of hope now for them.

YUGO missionary Tanya Ceas works with women in La Mesa prison while YUGO missionary Narcis Dragomir works with the men in the El Hongo Prison, east of Tijuana. All of our missionaries also work alongside Mexican nationals who minister in the prisons.

The infamous La Mesa Prison known as "El Pueblito" because of the little town that was built by the inmates on the inside of the prison. As of 2002, the little town has been destroyed and all inmates are in cells now.