Background: Many intensive care unit survivors (ICU) are confronted with undesirable and long-lasting impairments in physical, cognitive, and mental health, but not only patients are at risk of developing this post–intensive care syndrome (PICS). Family members can experience symptoms of depression, anxiety, and posttraumatic stress disorder (PTSD). This cluster of complications is called PICS–family. Objective: To describe the level of caregiver strain and posttraumatic stress–related symptoms in relatives of ICU survivors. Methods: We conducted a cohort study in a general hospital between July 2010 and May 2014. Relatives of ICU survivors, mechanically ventilated for > 48 h in the ICU, were asked to complete a questionnaire 3 months after discharge from critical care. Symptoms of PTSD and caregiving concerns were assessed using the Trauma Screening Questionnaire and the Caregiver Strain Index (CSI). Results: A total of 94 relatives visiting our post-ICU clinic completed the questionnaires. Twenty-one percent of the caregivers had a CSI score of 7 or more, indicating high levels of strain. Six percent had CSI scores indicating severe strain (CSI > 10). PTSD-related symptoms were seen in 21% of the caregivers. The mean time spent on caregiving was 10 h (interquartile range 6–17 h) per week. Conclusion: This study shows that relatives of ICU survivors could experience strain 3 months after hospital discharge and are at risk of developing PTSD-related symptoms. This complements existing data that relatives are at risk of psychological symptoms. Knowledge can lead to improvements and means to prevent these symptoms.