Judge Diane Schafer Goodstein was born in Dillon, South Carolina in 1955. She is the daughter of Joseph M. Schafer and Helen Schafer Mast.

Judge Goodstein attended elementary and secondary schools in South Carolina and received her bachelors' degree in 1978 from the University of North Carolina at Chapel Hill. She went on to obtain her Juris Doctorate Degree from the University of North Carolina School of Law in 1981.

She began her professional career as an associate in the firm of Goodstein, Bowling, Douglas & Phillips from 1981 to 1983. In 1983, she became a Partner/Vice President in the Summerville firm of Goodstein & Goodstein, P.A., the practice she shared with her husband, Arnold S. Goodstein until 1998. She served as the County Attorney for Dorchester County from 1986 to 1988. She is a former Board Member of the Greater Summerville Chamber of Commerce, Hospice of Charleston and My Sister's House. She was also a member of the South Carolina Bar Professional Responsibility Committee and a member of the Dorchester County Centennial Committee.

Judge Goodstein was elected by the South Carolina General Assembly to the position of Resident Circuit Judge for the First Judicial Circuit in May 1998. She has since been appointed to the Circuit Court Judges Advisory Committee and is a member of the Commission on Judicial Conduct.

As a member of the South Carolina Bar Association, Judge Goodstein has been a featured speaker at several seminars. She devotes her spare time to preparing area high school students for the South Carolina Mock Trial Competition. She is also a member of the Dorchester County Bar Association and the American Bar Association.

She is married to Summerville attorney and former Member of the House of Representatives, South Carolina Senator, and Department of Transportation Commissioner Arnold Samuel Goodstein. They have two children, Arnold Samuel Goodstein, II and Eve Schafer Goodstein. They are members of the Charleston Temple Kahal Kadosh Beth Elohim (KKBE).