Social workers are regularly obligated to put the needs of others above their own. This coupled with a tendency for social workers to engage with clients’ trauma, often lead to secondary traumatic stress (STS) disorder being an occupational hazard resulting from working to help those who have been traumatized. This study interrogated the prevalence of secondary traumatic stress among social workers handling traumatized service users and identifying ways that social work employers could assist their employees to mitigate the effects of STS among social workers. Relational theory and professional quality of life model were therefore adopted for this study. The paper used primary data sourced from 323 samples drawn from 1600 licentiate Members of the Chartered Institute of Social Work Practitioners of Nigeria as at 2022. Convenience random sampling technique was used. Relevant empirical literatures were also explored. Findings revealed that STS experienced by social workers and the cumulative effect of it affects service delivery to service-users most especially, STS affects their professional life which has unintended negative impact on service-users. The study however recommended that the issue of STS blindness among many social work organizations should be addressed; training on trauma-informed practices put in place vis-a-vis constant education, mitigation and funding devoted to this important subject through periodic interventive workshops and education.