Human trafficking, also known as modern-day slavery, is an egregious human rights violation associated with wide-ranging medical and mental health consequences. Because of the extensive health problems related to trafficking, health care providers play a critical role in identifying survivors and engaging them in ongoing care. Although guidelines for recognizing affected patients and a framework for developing response protocols in health care settings have been described, survivors' ongoing engagement in health care services is very challenging. High rates of disengagement, lost contact, premature termination, and attrition are common outcomes. For interventions to be effective in this marginalized population, challenges in engaging survivors in long-term therapeutic primary and mental health care must be better understood and overcome. This article uses the socioecological model of public health to identify barriers to engagement; offers evidence- and practice-based recommendations for overcoming these barriers; and proposes an interdisciplinary call to action for developing more flexible, adaptable models of care.