No, but a qualified professional is recommended. CPAs can be used to incorporate your business and prepare all forms required to obtain your Federal ID number and make your "Subchapter S" elections with the federal government and your state. CPAs are qualified to interact with other professionals and instruct them as to the requirements of their clients. However, CPAs should not play attorneys. Lawyers are needed to draw up shareholders' agreements, minutes and contracts based upon the advice given to you by your CPA. Lawyers reduce the advice to writing. Both a Lawyer and a CPA are valuable, necessary assets when starting your new business. You need both, but a CPA can provide the initial incorporation services.