This Healthcare Law Special Issue features five works from authors in the United States and Puerto Rico which discuss the changing US healthcare landscape as a result of the passage of the Patient Protection and Affordable Care Act of 2010 and the Health Care and Education Reconciliation Act of 2010 (colloquially lumped together as "Obamacare''). The collective effects of this legislation on the insurance, pharmaceutical, and healthcare markets remain difficult to gauge, as many of the provisions outlined by these two acts have come to fruition in just the past few years; such outcomes may not be fully realized and measurable for quite some time, and perhaps not until all of the requirements of such are totally and completely implemented. An example being the law's well-defined process of closing the Medicare Part D coverage gap, (also known as the "doughnut hole"), scheduled to be completed by 2020.