This cross-sectional study assessed the impact of a collaborative nursing/social worker case management (CM) intervention on emergency department (ED) use, health status, and health locus of control (HLOC) in a low-income uninsured population. Using a pre-post intervention design, key outcomes were assessed using paired t test. A statistically significant (48%) reduction in total ED visits resulted in an estimated charge avoidance of US$1,446,280. Physical health status improved significantly; however, mental health status and HLOC scores showed minimal change. This CM model may assist vulnerable groups in gaining access to care and improved health.