Background: This is a case study of an advanced practice nurse (APN) practice response to 2003 Medicare D-associated payer changes. Description: Case study of changes in population/services after implementation of Medicare D policy considerations. Study design: Case study with data at 3 time points and analyzed using descriptive statistics/central measures of tendency/dispersion. Results: Largest changes found to affect public sector recipients/practice solvency. Conclusions: Unintended consequences of healthcare policy change affect APN practice/health of vulnerable populations. Recommendations for entrepreneur APNs include supportive policy in addition to business preparation, education, and tools that generate safe strategies for alternate income streams during policy/payer changes. © 2010 American College of Nurse Practitioners.