In Ontario, all land development projects, from urban condominiums and housing subdivisions, to highway expansions and infrastructure projects, require heritage assessment and mitigation of impacts before approvals are granted.[2] Archaeological Services Inc. was established in 1980 to assist development proponents in meeting these requirements.[3] The company was founded by Chief Archaeologist and Managing Partner, Dr. Ronald F. Williamson, with Debbie Steiss (MA), Dr. Robert MacDonald, Robert Pihl (MA) and Martin Cooper (MA) joining as partners in 2002.[4]
The company ownership was transferred to a new generation of owners on October 1, 2016. The current Managing Partner is Dr. Robert MacDonald, who is joined by Dr. Katherine Hull, Lisa Merritt (MSc), Dr. Andrew Riddle, David Robertson (MA) and Rebecca Sciarra (MA) to form the leadership team. Dr. Ron Williamson and the original partners Martin Cooper, Robert Pihl and Deborah Steiss have retained an important advisory role within the company.[citation needed]
As of 2019, ASI employs approximately 67 full-time staff members and hires approximately 100 seasonal staff each field season. Most of the company's full-time archaeologists and many of the seasonal archaeologists are registered and licensed with the Ontario Ministry of Tourism, Culture and Sport, adhering to the ministry's licensing guidelines for consultant archaeologists.[6][7]
The Mantle Site: An Archaeological History of a Sixteenth Century Huron-Wendat Community (with Jennifer Birch), AltaMira Press (Series: Issues in Eastern Woodlands Archaeology, edited by Thomas Emerson and Timothy Pauketat), New York, 2012, 194p.[14]
Toronto: A Short Illustrated History of its First 12,000 Years. (Editor and author of one chapter entitled Before the Visitors). Lorimer Press, 2008. 128p.
The Archaeology of Bruce G. Trigger: Theoretical Empiricism. (Co-edited with Michael Bisson and co-author of Foreword and Introductory chapter), McGill-Queens University Press. 2006. Montreal, 291p.
Bones of the Ancestors: The Archaeology and Osteobiography of the Moatfield Ossuary. (Co-edited with Susan Pfeiffer and co-author of five chapters), Mercury Series Paper No. 163, Canadian Museum of Civilization. 2003. 351p and CD ROM.
Government on Fire: The History and Archaeology of Upper Canada's First Parliament Buildings. (Co-authored with Frank Dieterman) Toronto: eastendbooks, 2001. 118p.
Taming the Taxonomy: Toward a New Understanding of Great Lakes Archaeology. (Co-edited with Chris Watts and author of the Introduction) Proceedings of the Joint Symposium of the 1997 Ontario Archaeological Society and the Midwest Archaeological Conference, North York, Ontario. Toronto: eastendbooks, 1999, 416p.
The Archaeology of the Parsons Site: A Fifty Year Perspective. (Co-edited with David Robertson and co-author of three chapters). Ontario Archaeology, Volume 65/66, (edited volume), Toronto, 1998, 212p.
Legacy of Stone: Ancient Life on the Niagara Frontier. (Co-authored with Robert I. MacDonald). Toronto: eastendbooks, 1998. 168p. Second Printing, 2000.
The Myers Road Site (AiHb-13): A Prehistoric Iroquoian Village, Cambridge, Ontario, (Editor and co-authored four chapters). Occasional Publication of the London Chapter, Ontario Archaeological Society, Number 7, London, 1998. 216p.
Death at Snake Hill: The History and Archaeology of a War of 1812 Cemetery (with Paul Litt and Joseph Whitehorne). Toronto: Dundurn Press, 1993. 158p.
Snake Hill: An Investigation of a Military Cemetery from the War of 1812 (co-edited with Susan Pfeiffer; authored Introduction and co-authored two additional chapters). Toronto: Dundurn Press, 1991. 443p.