Private company
Callison
US-based architecture firm
Callison was an international architecture firm based in Seattle, Washington. Callison was founded by Tony Callison in 1975 and grew to 900 employees around the world prior to its acquisition by Arcadis NV in 2014. In October 2015, Callison was formally merged with another Arcadis subsidiary, RTKL Associates, to form CallisonRTKL headquartered in Baltimore, Maryland.2 Wikipedia text CC BY-SA 4.0
Last updated Oct 21, 2026.
Overview
- HeadquartersSeattle1
- Websitewww.callison.com
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Callison was an international architecture firm based in Seattle, Washington. Callison was founded by Tony Callison in 1975 and grew to 900 employees around the world prior to its acquisition by Arcadis NV in 2014. In October 2015, Callison was formally merged with another Arcadis subsidiary, RTKL Associates, to form CallisonRTKL headquartered in Baltimore, Maryland.2
Timeline
- 1975Founded Founded1
Links
- Websitewww.callison.com1
- WikipediaCallison
- WikidataQ5022764
Sources
The numbers on this page point here. Each one links to the record it came from.
- 1WikidataCallison on Wikidata
- 2WikipediaCallison on Wikipedia