The Canadian Auto Workers (CAW) union has reached a tentative agreement with Ford Motor Co. that follows the pattern established at General Motors Co. and Chrysler LLC this past spring while maintaining the company's manufacturing base in Canada. This agreement, however, allows for the closure of Ford's St. Thomas, Ontario, plant.

"Ford sells hundreds of thousands of vehicles in Canada each year and we must ensure that they continue to employ Canadians in the production of just as many...