Barbara M. Hamilton KC was judge of the Manitoba Court of King's Bench.
Until 1980, she practised general law with the firm of Martens, Kripiakevich, Dennehy, Parfeniuk & Ernst.
From 1980 until 1987, she practised mainly corporate and commercial law with the firm of Scarth, Simonsen, Dooley, Olsen & Wiens, with whom she became a partner in 1985.
From 1987 until her appointment to the bench, Hamilton was a partner with the firm Aikins, MacAulay & Thorvaldson.
She has acted as a bencher, vice-president (1991–1992) and president (1992–1993) of the Law Society of Manitoba.