Johnston is a museum director, curator, writer and educator who's worked in museums in Minneapolis, New York, Ireland, Northern Ireland, Georgia, and North Dakota. She has curated more than 300 artists’ projects and considers herself an arts activist. Her work has been published in several books, journals and periodicals including OnCurating, CIRCA, and Open Engagement. She recently finished her PhD in curating and museology at the University of Ulster in Belfast, Northern Ireland, UK, focusing on Slow Curating. She is currently the Executive Director at Rochester Art Center in Rochester, Minnesota.