A Health Savings Account, or HSA, is a financial account that allows individuals and families to save funds for day-to-day health care expenses while holding a catastrophic insurance policy for more costly care. While first introduced in January 2004, the Internal Revenue Service continues to release clarifying notices to help employers and individuals make the best use of the options available to them through HSAs. This policy brief offers a discussion of the advantages of HSAs relative to Individual Retirement Accounts (IRAs) and other savings options. As well, the brief includes an overview of the latest three notices – 2008-51, 2008-52, and 2008-59 – all released in recent months. The guidance includes such topics as: the ability to rollover funds from an IRA into an HSA; the “testing period” for such rollovers; rules for individual and family eligibility; rules for contribution eligibility; rules for tax reporting; rules for HSA account transactions; rules for Medicare beneficiaries; penalties for misuse. Those seeking to better understand how HSAs function and whether an HSA is right for them should be able to review the information contained in this policy brief and quickly gain a far greater sense of the workings of this important health care tool.