Aggression theories and cross-sectional studies imply an escalatory pattern of aggressive behaviors; however, this has not been investigated in a follow-up study.To investigate whether bullying or conflicts are antecedents of threats and physical violence, and whether threats mediate the relationship between bullying or conflicts and violence. Lastly, it was explored whether associations could be explained through the effect of emotional exhaustion.Survey data was collected from a follow-up sample of 3,584 employees from four human service sectors, namely psychiatry, special schools, eldercare, and the prison and probation services. The main analysis uses hierarchical logistic regression.The analyses showed that frequent /intense conflicts, not bullying, at baseline were significantly related to higher exposure rates of threats (OR = 4.98, CI = [3.19-7.76]) and violence (OR = 3.01, CI = [1.96-4.76]) at follow-up. Emotional exhaustion was not confirmed as a substantial mediator. However, the proportion mediated by threats was significant (70%) for the relationship between frequent /intense conflicts and violence.This study finds that aggressive workplace behaviors may indeed escalate, particularly within a similar victim-perpetrator relationship, such as between employees and clients. The study highlights the need for de-escalation techniques that transcend specific encounters, recognizing that aggressive behavior may escalate over time.