Enrolled agents are individuals licensed by the federal government for the benefits of the taxpayer. The job of the EA is to guide the taxpayer at administrative levels of the IRS. They have to be highly competent in all areas of taxes.
Since 1884, when they were sanctioned by Congress to help taxpayers in dealings with the treasury department, enrolled agents have been adding to their repertoire. They, CPAs and attorneys, are the only ones allowed to legally represent you in front of the IRS. The advantage of having an enrolled agent, unlike CPAs and attorneys, is that they are IRS approved. They may be more competent in the field of taxes then the other two types of tax professionals.
To become an enrolled agent, a person has to be an employee of the IRS for at least five years and have demonstrated competence with IRS regulation and codes or have taken a very rigorous two day examination that tests everything from individual taxes to corporate taxes followed by a thorough background check. Once a person has become an enrolled agent, they are required to take a 72 hour course in continuing professional education every three years.