There are four main organizations that grant business valuation credentials. Each organization has different requirements.
ASA & IBA
Credentials granted from the American Society of Appraisal (ASA) and Institute of Business Appraisers (IBA) are held in high regard since their exams are difficult and have lower passing rates, and peer review of actual appraisal reports is required.
AICPA & NACVA
Credentials are offered by the American Institute of Certified Public Accountants (AICPA) and National Association of Certified Valuation Analysts (NACVA).