The show I’m currently writing is very dialogue-driven so that sense of rhythm has to be its foundation. So when writing the scene, I figure out the intent and then just go. Some scenes happen quickly, others take more time and the best part about the painstaking ones are moments of going through it over and over and finding out what’s muddling up the rhythm. It’s usually loose words or unnecessary lines. Once those are cut or words are replaced and fixed up, it flows.

Luckily, we’ve cast actors who are very respectful of the script. They say it word for word (and for the first time ever, I’m absolutely comfortable correcting them if they change something I’ve written). Also, if a line doesn’t feel right to them, we’ll discuss and if the point is valid, we’ll change something around – as long as it doesn’t interrupt the flow of the scene.

Just like the D.O.P has to make it easy on the eye - part of a writer's job is to make it easy on the ear & actors will love you for it. Rhythm is essential.

I most definitely use rhythm in my writing. It establishes a recognizable pattern in the mind of the listener/reader. This results in anticipation, helping them feel more engaged the scene or conversation.

Rhythm is a major part of the plays I have written. Lines meant to be spoken have that timing and flow. The rhythm of lines meant to be read are different I think. Visual tricks and advantages to be taken of how we parse text. But in general of course rhythm is important... iambic pentameter was invented for a reason.

I also write for games so how to write when the flow of the narrative is not the flow of the words that will be read or the words that will be spoken is more challenging.

In addition to what @Erin posted... I just finished writing a spec pilot based on a friend's life/character, he's a standup, and I ran into a rhythm issue with a chunk of dialogue. There's a section with three questions and three responses. They go from single word question/answers to multi-word. My buddy gave me notes and wanted to add a techno fact to the first answer which had just been a single question. As we were doing the notes I didn't have a problem with it. It was only four words. But when I went back and was making the changes that addition really bugged me, and it took me a while to figure out why. It threw a wrench into the rhythm of the exchange. When I wrote it the exchange just flowed out, and it wasn't until it became clunky with the added clause that I realized there was a definite rhythm to that section. Consciously I'm aware of the rule of 3s and progression, etc. But through all the years of writing and improv comedy that stuff has become second nature. It's made me more careful about rewrite notes.

Thanks all for your comments. In thinking about it, I'm guessing a TV writer must have an even greater awareness of rhythm in dialogue simply because most TV is more dialogue driven than movies.

In general, it's an interesting way to distinguish between characters, zeroing in on each one's unique rhythmic patterns.

I never thought about this consciously but (like many things I do) I've been writing rhythmically by instinct. It just felt right.

It might have something to do with musical training. I've been a songwriter for years now, recorded albums, played a bazillion shows etc...

That's got to help.