Ellen Barry has worked as an advocate for criminal justice, racial justice and human rights for over 35 years. She founded Legal Services for Prisoners with Children (LSPC), a non-profit organization which has advocated on behalf of incarcerated parents, their children and family members and was executive director of that organization from 1978 to 2001. From 2002 to 2012, she worked as a consultant on criminal justice and other human rights issues. She is a founding member of Critical Resistance, a US-based movement which challenges the growth of the prison industrial complex and its detrimental effect on education, health and human services. She serves as an activist representative for the Criminal Justice Initiative (CJI), as co-chair of the board of the National Network for Women in Prison (NNWP), and as a member of the Prison Creative Arts Project Advisory Board. 

She is a former member of the California State Bar Section on the Delivery of Legal Services, past co-chair of the State Bar Committee on Legal Services for Prisoners, and served on the Statewide Commission on Female Inmates and Parolees (SCR 33 Commission which issued statewide report on women in California prisons, 1992). She has written and spoken extensively on issues affecting prisoners, their children and family members. In 1997, she received a Soros Senior Justice Fellowship to work on behalf of prisoners, their children and family members. In 1998, she was awarded a MacArthur "Genius" Fellowship. In 2005 and again in 2007, she was nominated for the Nobel Peace Prize along with 999 other women activists around the world.