The agreement spares the late-night shows that would immediately have gone dark without writers, and allows the networks to pursue their schedules for the upcoming TV season without interruption. Movie production would have felt a strike's sting more gradually.
Guild members voted overwhelmingly last month to authorize a strike, and the WGA could have called for an immediate walkout Tuesday absent a deal. The previous writers' strike exacted an estimated $2 billion toll on the state. The producers group said the 2007-08 strike cost writers $287 million in lost compensation.
Russ DeVol, the chief research officer at the Milken Institute, estimated a strike of similar duration would have cost California $2.5 billion today.
After the 2007-08 strike, the two sides reached agreements in 2010 and 2013, but TV writers in particular have seen their earnings slide since then and wanted to claw back some of those losses.
Driving the dispute were changes in how television is distributed, with streaming platforms, including Netflix and Amazon, joining broadcast and cable TV and rising in importance.
More outlets have led to more shows, but the TV season model is greatly changed. Despite the fact that there are more series than ever -- 455 this season, more than double the number six years ago -- shows run for fewer episodes than the traditional 22-24 episode broadcast series.
Short seasons of eight, 10 or 12 episodes means less pay for writers whose payment is structured on a per-episode basis.
To address that, the guild said it won additional compensation for writers who spend more than 2.4 weeks working on a script.