When we talk about movies and TV, we usually fixate on actors and directors — but without writers, the whole ship goes down. And once again, Hollywood’s writers are on the verge of a strike, which, if it happens, would be the sixth writers strike in Hollywood’s history.

On April 24, the Writers Guild of America, the union that represents entertainment writers across the country, voted by a wide margin to authorize a strike. On April 25, the union resumes talks that could avert the strike — if the studios agree to their demands, or if a compromise is reached. If not, WGA members will likely walk off sets and stop work starting May 2. In the past, WGA strikes have lasted anywhere from two to 22 weeks, and have had far-reaching consequences for the entertainment industry.

Hollywood union strikes sit at the intersection of the entertainment business and American labor law — two things that don’t often overlap for the average TV or movie viewer. But the strike, if it happens, could affect what makes it to those viewers’ screens in the coming months.

Here’s what the writers are seeking, why they’re seeking it, and what could be at stake.

What is the Writers Guild of America?

Hollywood lives and dies by its labor unions, and the WGA is the union that represents the writers, most of whom work in TV and film. (Other unions, like the Directors Guild of America and the Screen Actors Guild/American Federation of Television and Radio Artists, represent different segments of the entertainment industry.)

The WGA is actually the joint efforts of two different groups: WGA West and WGA East, which are divided roughly by the Mississippi River. The two guilds operate independently, but they join together to give annual awards, register scripts to prove document authorship (similar to a trademark), and determine how writers will be credited.

And — most importantly right now — the two groups participate in collective bargaining with the Alliance of Motion Picture and Television Producers for wages, benefits, and other considerations. The AMPTP represents more than 350 production companies and studios, including the Big Six: Paramount Pictures, Sony Pictures, 20th Century Fox, Universal Pictures, Walt Disney Pictures, and Warner Bros. Pictures, which produce both movies and TV shows.

The last time the WGA held a strike was 2007, and it concluded on February 12, 2008. Most viewers remember that time as moderately annoying, with many scripted shows forced to cut their seasons short, some late-night shows going off the air, and some reality shows getting longer seasons or new seasons. (Episodes of Donald Trump’s new show The Celebrity Apprentice — a twist on his non-famous-person Apprentice, which had been shelved by NBC due to low ratings — took the place previously occupied by The Office and Scrubs, which had to shorten their seasons.)

But for writers in the industry, it was an important moment: Streaming services like Netflix, Amazon, and Hulu, then still in their infancy, were about to take over TV in a way almost nobody expected, and the strike gained them jurisdiction over the new form of entertainment, as well as at least some cut of the profits in the form of residuals.

The impending 2017 strike could be as irritating to viewers, but the stakes are even higher this time, with many writers struggling financially as a result of changes in the industry.

Why is the WGA threatening to strike? What do the writers hope to accomplish?

There are two major reasons for the strike. First, studio profits have been rising over the past few years, particularly in TV — but many writers (especially those who earn middle-class wages) have seen their compensation go down, in some cases rather sharply. So the union wants the studios to raise wages. And second, the WGA’s pension and health plans are on the verge of imploding, and the union wants studios to contribute more to those plans.

The WGA distributed data in its 2017 contract bulletin that helps explain the first of these demands. The decline in writers’ pay is tied to changes in the TV industry, many of which are clear to the average TV viewer.

You’re not imagining it: There really are more TV shows than ever. In 2013-’14, there were 262 scripted TV shows on the air; in 2015-’16, that number had increased to 301. There are several reasons for this increase, including a proliferation of streaming services with original programming, such as Netflix and Amazon, as well as an uptick in scripted content on niche TV networks.

With more TV for audiences to choose from and a broadened variety of ways for them to watch (broadcast, streaming, and more), there’s been an important shift in the industry: TV seasons are shorter than ever. Whereas most TV shows in the past ran about 20 to 22 episodes, today many series have only eight or 10 episodes per season. This has generally been a boon for the quality of TV, with actors, writers, and directors who formerly worked only in film migrating to TV because the time commitment is more manageable (think of True Detective and Big Little Lies, for instance). But it has led to problems for TV writers, who are usually paid per episode: This season shrinkage can have a pronounced effect on their total compensation.

In the 2013-’14 TV season, 165 shows aired between two and 13 episodes; by 2015-’16, that number had jumped by 40, to 205. In that time, the number of shows airing more than 14 episodes has remained nearly flat (from 97 to 96). The gap between seasons has grown wider as well. FX’s Fargo, for instance, aired its second season in the fall of 2015, but its third season didn’t debut until April 2017. Similarly, True Detective aired its second season in the fall of 2015, but has yet to announce whether a third season will even exist, though one is rumored.

Now, these changes can be beneficial for both writers and producers. For writers, it encourages writing tighter, more narratively coherent TV, which can be more creatively satisfying than keeping storylines spinning in order to fill episodes. And for producers, it means more time between seasons to write scripts before production begins. So a writer might spend three weeks on an episode, rather than one or two — which can result in better shows, with more critical acclaim and awards potential.

But the problem is that writers’ per-episode compensation hasn’t changed, which means they can receive the same amount of money for three or more weeks of work writing an episode that they typically would have received for two or less. That means the money writers would have earned for two weeks’ work is now stretched over three or more — so they’re essentially getting paid less for the same work.

And thus experienced writers who in the past would have been paid more than the union’s minimum agreement are now earning the minimum. Between 2013-’14 and 2015-’16, writers (who typically are credited as producers on TV) earning the minimum rose substantially: executive producers and showrunners by 8 percent, supervising and co-executive producers by 16 percent, consulting producers by 24 percent, co-producers by 32 percent, and producers by 49 percent — for an average of 20 percent.

And there’s an important added wrinkle: Many staff writers on TV shows are held to exclusive contracts during the duration of the show’s run — whether or not they’re currently working on scripts for the show. So writers are not permitted under their contract to find other television work during a show’s break to fill the compensation gap.

Typically, writers would also depend on residuals in syndication to help pay the bills, but reruns are no longer common for many shows. Even big hits like Modern Family have struggled to pull in the kind of syndication ratings that would ensure a long run in that market (as, say, Seinfeld has enjoyed). Also, residuals are set relatively low for streaming content compared with the amount writers earn for network TV reruns. (Gaining residuals for streaming services was the major issue during the 2007-’08 strike, when the offer on the table to writers was receiving zero.)

To review: Many writers get paid less overall during TV seasons, the money they earn during breaks has decreased, and they aren’t free to work on other shows during breaks — all of which has had a sizable effect on wages. Between 2013-’14 and 2015-’16, writers saw their median earnings drop sizably: co-producers and producers by 19 percent, supervising producers by 12 percent, co-executive producers by 26 percent, consulting producers by 23 percent, executive producers by 8 percent, and showrunners by 21 percent. The average wage depression for writers was 25 percent.

By contrast, in 2016, the six biggest studios that belong to the AMPTP reported $51 billion in operating profits, which represents about double their profits 10 years ago (the last time the WGA went on strike).

A second important problem on which the guild is focused is its nearly bankrupt health care plan, which has a disastrous projected deficit over the next three years of $145 million. If it continues on its current track, the health plan will go broke by the end of 2020. This is, of course, a big problem — and the union wants studios to contribute more to the plan.

What will happen if the WGA goes on strike?

Under the strike, all members of the WGA will cease writing and producing on AMPTP projects (and the guild has promised the strike, if no agreement is reached, will commence May 2). This has far-reaching implications in the entertainment industry — especially in TV, where writers are often in charge, serving as producers and directors as well as writers. (In film, writers are usually less involved with the final product, and the film industry is typically less affected by strikes, since many completed screenplays exist already. However, many films rushed into production before the 2007 strike, resulting in movies that were shot without finished screenplays, such as the second Transformers film.)

Some TV series and films with completed scripts will likely continue shooting, but writers will stop work on scripts and are supposed to step away from production duties. (This could end up being a contentious point; during the 2007 strike, some showrunners continued with production duties.) Depending on the strike’s duration, some shows may be forced to end their seasons early, the summer TV season could be affected, and, if it lasts long enough, the fall TV season could see repercussions as well — all of which has serious implications for ad buyers and networks.

If networks can’t promise full seasons of upcoming shows to ad buyers, their ad revenues will likely be reduced — an especially big deal given that TV networks managed to garner more than $9 billion in ad sales last year. Those are the industry’s biggest numbers in three years, a statistic heralded as a sign that even among streaming services, the advertising industry sees value in capturing the broadcast TV audience.

And if broadcast TV is forced to air reruns — especially in a time when virtually every show is available digitally somewhere — their attractiveness to advertisers will go down. (Streaming services like Netflix and Amazon, which have a back catalog of shows available to them and are less dependent on new releases and advertisers for revenue, would likely see fewer effects than broadcast TV.)

Additionally, late-night shows such as Saturday Night Live and The Tonight Show — which generate new scripts on a daily or weekly basis — could go dark for the duration of the strike, and start their summer recess early if the strike lasts long enough. On April 15, SNL, which is riding a wave of boosted ratings due to renewed interest in political satire, began airing its show live on both coasts (instead of just the East Coast) for the last four episodes of the season; the strike could knock out its final three episodes entirely.

The strike also affects ordinary people who work in the industry, many of whom struggle financially even when they’re working, or who are comfortable but not affluent. Striking writers would go unpaid for the duration of the strike, which can be difficult for those who ordinarily struggle to get by. Shows that stop production may be forced to lay off their production staff, which can include everyone from camera operators and art directors to interns and production assistants. And members of other entertainment unions, such as the Screen Actors Guild and the Directors Guild of America, historically tend to support union strikes and may also be reticent to cross picket lines, further complicating the strike.

How long the possible 2017 strike lasts would depend on a number of factors, including how much each side is willing to compromise to avoid loss in revenues and income.

Why can’t TV shows just hire other writers to work during the strike?

When AMPTP members sign a contract with the WGA, they agree to only hire writers who are WGA members. Similarly, WGA members agree to only work with companies who have signed the contract. That’s the basic agreement, and it’s what sets many independent production companies apart from the wealthier, bigger studios.

This is significant because virtually all of the major writers in Hollywood are WGA members — and that’s what gives the union its bargaining power. For the length of time that the WGA is on strike, AMPTP companies are reticent to hire other writers, and they can’t get WGA writers to work for them. So they essentially have no content to sell to audiences or attract advertisers.

During the 2007-’08 strike, a small number of soap operas (including As the World Turns and General Hospital) did hire non-union writers to work on scripts. But strikebreakers face fines and disciplinary action from the union, which can have long-term effects on their career prospects in the industry. And non-union writers who fill in for striking WGA members could face repercussions if they want to later apply for WGA membership, which is the best way to get steady work in Hollywood as a writer.

Has the WGA ever held a strike before?

Yes. The WGA’s contract with the AMPTP comes up for renewal roughly every three years, and they’ve opted to strike five times since they were founded (WGA East in 1951 and WGA West in 1954).

The last WGA strike began November 5, 2007, and concluded on February 12, 2008, lasting about 14 weeks. The main issue was residual payments for DVD sales as well as residual payment for and jurisdiction over streaming services, which at the time were still in their infancy. As a result of the strike, a number of scripted shows shortened their seasons, while some unscripted reality shows (including The Amazing Race and Big Brother) aired more episodes. Many late-night shows were delayed or interrupted by the strike.

main issue was residual payments for DVD sales as well as residual payment for and jurisdiction over streaming services, which at the time were still in their infancy. As a result of the strike, a number of scripted shows shortened their seasons, while some unscripted reality shows (including The Amazing Race and Big Brother) aired more episodes. Many late-night shows were delayed or interrupted by the strike. In 1988, the WGA’s longest strike — and the longest union strike in Hollywood — lasted 22 weeks, from March 7 to August 7. Writers were arguing for increased residuals for hour-long syndicated shows as well as expanded creative rights, such as choosing directors and actors for some projects. They eventually won the latter for films and TV movies, but compromised on the former in favor of the studios’ preferred model of sliding-scale residuals. The strike caused the major TV networks to delay the start of the fall 1988 TV season (which typically would have begun in late September) by a month or more.

In March 1985, a two-week strike — mostly over residual payments for what was still considered the “burgeoning videocassette market” — briefly suspended the broadcasts of several late-night shows, including The Late Show With David Letterman, Johnny Carson’s Tonight Show, and Saturday Night Live.

The WGA held a three-month strike in summer 1981, which successfully established that writers would be compensated for home video and “pay TV.” The strike slightly delayed the fall TV season, but the guild reached interim agreements with producers of many live TV shows that allowed them to remain on the air.

The second-longest strike in the WGA’s history took place in 1960 and lasted from January to June. The union won the right to a share of the studios’ revenue when movies were leased or sold to TV. Studios were also required to pay into the pension and health fund, which is a focal point of the 2017 negotiations. The Screen Actors Guild held a parallel six-week strike (which ended before the writers left the picket line), led by then-SAG president Ronald Reagan.

Whether the WGA aims to add another chapter to this history is the question it will likely determine by May 1, when the current contract expires. WGA strikes have been generally effective, and it’s clear that a lot has changed about the entertainment market since the last strike 10 years ago. The question is whether the people behind that market can agree on the terms going forward.