Emergency medical service (EMS) personnel are subjected to intense and traumatic workplace scenarios, which place workers at risk for developing trauma reactions that lead to mental health conditions such as posttraumatic stress disorder (PTSD), depression, and anxiety. However, little research has explored the impact of EMS workers' work-related stress on their romantic partners despite evidence supporting the impacts of secondary traumatic stress (STS). This study explored the relationship between EMS workers' self-reported PTSD symptomology and EMS workers' romantic partners' self-reported PTSD symptomology, relationship satisfaction, and social support. The sample consisted of 30 couples, 13 married and 17 unmarried. Findings confirmed that EMS workers with more severe PTSD symptomology were in relationships with partners who also reported higher symptomology. Additionally, increased PTSD severity among EMS workers was associated with partners' decreased satisfaction with the quality of social support. This study confirms the effect of STS among EMS workers and their partners and highlights practical applications for improving the mental health of EMS workers and their partners. Implications for these findings include assessing partners for dysphoric arousal, psychoeducation, counseling assistance to EMS personnel, and focusing on opportunities for vicarious posttraumatic growth among couples are discussed. [ABSTRACT FROM AUTHOR]