Purpose: Suicide prevention and intervention in prisons is a challenge. Prisons were not designed to be clinical facilities, yet with the growing numbers of people who face mental health challenges in prisons, staff require knowledge and skills to adequately address mental health crises, especially suicide. This study aims to: describe trends in suicide attempts and completions within one state's prison system and measure staff knowledge and preparedness to address suicide. Design/methodology/approach: This research uses a nonexperimental research design and two data sources. Administrative data from 2000 to 2017 on serious suicide attempts and completions were analyzed, and all correctional staff employed in the state's Department of Corrections were surveyed at one point in time. Univariate and bivariate analyses were conducted. Findings: The number of serious suicide attempts trended up but completed suicides decreased. Correctional staff demonstrated high suicide knowledge of risk factors and warning signs of suicide. Staff who viewed a media-based suicide training displayed significantly more knowledge of suicide and perceived greater preparedness compared to staff who did not or did not recall viewing the training. Originality/value: Corrections staff play a key role in preventing suicides in prison. Innovative intervention is needed to increase suicide awareness, improve communication and enhance prevention skills.