Well, a union is a group of people that collectively bargain for wages, work conditions, and benefits. What that means is that the workers stand together, and then pay rates are discussed with the owners. Law requires somewhat transparency with the actual books, so they bargain with facts. Cost of living is taken into account, and when they are all done, a contract that the workers and owners agreed on is law. In non union businesses, the employer sets a wage and work conditions, and then tries to hire people. Between the two models, guess which one will have higher pay? Pay is also only part of the equation, because in a union contract, benefits are spelled out as well, and are a large portion of the overall per hour number. On top of that, most unions provide training, sometimes mandatory training, to stay on top of changing technologies and to make their members more valuable to the employer. It's a give and take thing when done right.