The National Association for Professional Gerontologists certification mark awards credentials to those who demonstrate that they possess a core body of Gerontological knowledge. NAPG defines core Gerontological knowledge as including the following: a broad background in the social, psychological, and physical/biological aspects of aging, including theoretical concepts; knowledge of practice concepts in working with older adults, including ethical issues, and demonstrated mastery of gerontology skills and competencies. Those who meet the credentialing requirements are awarded the CPG certification.