My first thought when encountering the word "accreditation", I must admit, is that it's hard to spell. My second thought, which is more an impression, is another A-word: admiration.
Accreditation is a voluntary method of quality assurance developed more than 100 years ago by American universities and secondary schools, and designed primarily to distinguish schools adhering to a set of educational standards. The accreditation process is also known in terms of its ability to effectively drive student performance and continuous improvement in education. But such definitions, though accurate, are incomplete.
NRPA has its own definition, with clear roots from the world of academia, and also offers two flavors: