If you live in a midsize American city, you’ve probably noticed that an increasing share of local services are provided by chain establishments such as the Cheesecake Factory and Wegmans. Why? It’s because the industrial revolution that transformed U.S. manufacturing more than a century ago is finally reaching many local services, which had long resisted standardization.

…Locals sometimes lament when a new chain in town bears down on a mom-and-pop shop. But in the past four decades industries in which top firms have grown in share have created many more jobs than ones where market share is dispersed among small peers. Companies that have taken advantage of the industrial revolution in services grow by expanding into smaller cities or exurbs, and provide competition to previously dominant local monopolists. This brings jobs, as well as cheaper and higher quality services from groceries to health care, to areas that need them most.

In contrast, employment has shrunk in sectors still dominated by small independent operators, such as plumbing and electrical wiring. Over the past four decades, the growth of the top 10% of firms in local services in a given year has accounted for 80% of the cumulative wage and employment growth in the U.S.

The rise in national industry concentration in the US between 1977 and 2013 is driven by a new industrial revolution in three broad non-traded sectors: services, retail, and wholesale. Sectors where national concentration is rising have increased their share of employment, and the expansion is entirely driven by the number of local markets served by firms. Firm employment per market has either increased slightly at the MSA level, or decreased substantially at the county or establishment levels. In industries with increasing concentration, the expansion into more markets is more pronounced for the top 10% firms, but is present for the bottom 90% as well. These trends have not been accompanied by economy-wide concentration. Top U.S. firms are increasingly specialized in sectors with rising industry concentration, but their aggregate employment share has remained roughly stable. We argue that these facts are consistent with the availability of a new set of fixed-cost technologies that enable adopters to produce at lower marginal costs in all markets. We present a simple model of firm size and market entry to describe the menu of new technologies and trace its implications.