The study population will consist of up to 5,000 persons with pain disorders and up to 5,000 healthy volunteers, who seek to participate in research protocols at NIH, primarily those sponsored by NCCIH Division of Intramural Research investigators. Human beings of adolescence age or older (greater than or equal to 12 years) that are willing to provide assent and/or consent may participate in the study. This protocol is open to volunteers of any ethnicity, gender, or nationality.