I own a US-based expert witness firm. My employees are US citizens and live and work in the US. We have a project consulting for the Government of Canada, on a case based in Canada, suing a Canadian company. We are the only US citizens involved and we will not enter Canada for the project. What taxes do we need to settle with the Government of Canada? I assume we file as normal and count the income as US income, but Canadian tax code seems to be even more difficult than US code, so am unsure.