When TV networks started producing scripted dramas and sitcoms in the 1950s, the studios "controlled all facets of production, from conception onward," says Cindy Y. Hong in Slate. Writers were mostly hired grunts, and only experienced TV executives pitched new shows. How did we get from the top-down studio system to today, where the "showrunners" who shape every facet of a TV show — including writing — have become well-known figures in their own right, sometimes rivaling the show's stars? Here's an excerpt:

Mary Tyler Moore was one of the first shows to give writers real creative freedom.... At the same time, audiences began to expect richer characters and plotlines. To keep a coherent vision, hit shows like Hill Street Blues began to rely on staff writers over contract writers. As writers became more critical to keeping shows on air, they were given more production responsibilities. Soon, studios even allowed writers to create new shows — and then to stay on to shape the shows they envisioned. The writer-executive producer was born. 

But in an era of producer credit proliferation... "showrunner" became natural shorthand for the person who literally runs the show. Variety started using "showrunner" to describe producers in 1992.

Read the entire article in Slate.