Typically you incorporate union representatives onto boards of companies, make the members shareholders etc. You tie incentive structures together.
Even so, I'm a reject your framing to a certain degree. Employees, and by extension labor unions, typically want to see the company they work at succeed. Labor always pays the price, e.g. forgoing wages during a strike.
And even when a deal is struck, employees often put the interest of the company ahead of their own, e.g. trading away already agreed upon wage increases in a labor contract in order to keep the company solvent.
Are there examples of both situations? Of course! I've seen both first hand, but it certainly isn't completely one or the other. Some companies have a good relationship with their unions, others are very antagonistic.
Even so, I'm a reject your framing to a certain degree. Employees, and by extension labor unions, typically want to see the company they work at succeed. Labor always pays the price, e.g. forgoing wages during a strike.
And even when a deal is struck, employees often put the interest of the company ahead of their own, e.g. trading away already agreed upon wage increases in a labor contract in order to keep the company solvent.
Are there examples of both situations? Of course! I've seen both first hand, but it certainly isn't completely one or the other. Some companies have a good relationship with their unions, others are very antagonistic.