I attended a class by Josi Kilpack on pacing. Some of the elements might seem obvious, but other points she brought up were less so ... to me. Obviously, pacing depends upon genre. We expect certain kinds of stories to pace faster than others. You need to consider who you're writing to, when deciding how to pace your tale.
I remember years ago (back when I read Stephen King), and my late husband brought home the book Salem's Lot. This book does an incredible job with its pacing and has the ability to scare the crap out of you by establishing normal and then breaking it. The way my husband described the book was that King drew you slowly into the story and then grabbed you by the throat and dragged you the rest of the way through it.
There are a variety of techniques for packing your story. Punctuation does a lot for it. Longer, more expository paragraphs will slow the pace down. Shorter sentences and paragraphs will speed it up. Dialoge tends to speed things up, while too many tags or beats can slow it down.
Something that came up in the discussion was the use of prologues. Evidently studies indicate readers don't read them, so they're discouraged. Makes sense. We shouldn't write things people skip. On my WIP #1, after receiving some critiques suggesting I'd started the story in the wrong place (there was an inciting event that everyone--including me--missed), I pulled a scene from Part 2 and stuck it in the beginning and called it a prologue.
And got blasted for having a prologue. However, what I'd done wasn't really a prologue ... it was a flashforward. Duh. If I wanted to I could leave it there and just call it chapter 1 and on chapter 2 add "three months earlier". That's not what I'm going to do, but it's nice to know that it was a technique I could use if I thought the story would work better.
Bottom line is that flashbacks and flash forwards are pacing techniques, since they slow the pace down.
How do you handle pacing? Do you have any types that you particularly like to use?