I was a rank-and-file worker at a company with a good steward structure years ago, so I knew something about how it worked. After I began working as a union representative for Service Employees (SEIU) Local 660, I was assigned to Harbor-UCLA Medical Center in Los Angeles. I saw immediately that the union there was weak.

Management often goes after workers who appear to be weak or disadvantaged. Gregg Shotwell, who works at a Delphi auto parts plant in Coopersville, Michigan, tells how members protected one of their own.

At Verizon, the largest phone company in the United States, the unions chose a work-to-rule strategy to fight extreme concession demands in 2003...