Last year, Massachusetts enacted a sweeping reform of its health insurance system, in an attempt to insure nearly all residents of the state. Highlights of the reform include employer assessments to encourage employers to provide insurance to their employees, a government subsidized insurance system for low income adults and an individual mandate that requires all adults in the state to purchase insurance or face a tax penalty. The reform is being implemented primarily by a new state authority called the Commonwealth Health Insurance Connector Authority. Massachusetts is contending with great challenges as stakeholders present conflicting views of how to implement the reform. These challenges include finding ways to encourage employer involvement without violating federal laws that prevent state regulation of employee benefits programs; balancing costs to enrollees against costs to government for subsidized programs; educating residents of the state about the new law; ensuring that the individual mandate encourages nearly universal participation while not punishing those who cannot afford insurance; setting minimum standards for insurance quality and controlling healthcare costs. Massachusetts’ experience may provide guidance to other policy makers and advocates as they develop and implement the reforms pending in other states and on the national level.