Professional certification can be defined as a voluntary process by which a professional association or organization measures (against an agreed upon set of professional practice standards) and reports on the degree on competence of individual practitioners. The intent of certification is to inform the public that individuals who have achieved certification have demonstrated a particular degree of knowledge and skill, thus offering some degree of public protection. It offers title protection, as only those who are certified may use a particular title. Functionally, professional certification constitutes a formal and public definition of a profession.

One outcome of professional certification is the ability to distinguish between those who have demonstrated competency, in an agreed upon manner, and those who have not. Another is the promotion of ongoing professional competency. One of the primary reasons certification is supported by so many professional groups is that it can enhance the reputation and positive public image of a profession while seeking to protect the public from incompetent practitioners.

Typically, a professional is required to be judged competent by their peers, by a predetermined criterion and method, before they can practice a profession. This is most often accomplished by a means of a professional certification exam. A professional certification exam also serves as a benchmark of excellence upon which new knowledge, methods and technology can be systematically integrated into the professional practice as the exam is updated and revised across time and place.

The development of standards for professional practice (as indicated by competency and performance standards), and perhaps formal certification, promotes several immediate, and highly desirable, outcomes. It establishes a basis for selecting new members into the profession. It establishes a sound basis for faculty members to train new professionals. It provides a basis for employers to hire professional with the specific knowledge and skill required to satisfy organizational demands. It provides a clear criterion for supervisors to judge the work performance of, and to assist in upgrading the knowledge and skill of established practitioners.

Essentially, the processes of developing professional practice standards, competency and performance criteria, and certification and assessment protocols are expected to achieve two important outcomes. First, is the explicit commitment on the part of a profession to continuously upgrade the knowledge, skill, performance and ethical behavior of its members. The second is the on-going effort to inform the profession's public(s) of this effort so they will have increased knowledge of and confidence in the profession's members.