Why did GM, U.S. Steel, GE, and other large, oligopolistic corporations agree to unionization? Part of the answer, at least for GM and the four major rubber corporations, was the factory occupations in Flint, Detroit, Cleveland, and Akron: they preferred peaceful organization to such baptisms of fire. And there may have been another equally compelling reason. Collective bargaining is one way to make labor a predictable factor in production. Of course, unionization obliged these major industrial corporations to yield higher money wages and assume the burden of the social wage (benefits), especially when the New Deal funds that provided elements of the social wage through federal taxation had been exhausted. On the other hand, the contract provision that addressed shop floor grievances through negotiation and arbitration was less disruptive and costly than strikes, slowdowns, and sabotage. The unions traded their autonomy for job security and a private social welfare arrangement. Contracts increasingly banned strikes for the life of the agreement. Equally important, the union often became an ally of the company in matters of worker discipline.