It's hard to not be amazed at the sheer volume of short fiction stories that are professionally published each year. Even if you only consider the speculative fiction genres—science fiction, fantasy and horror—the number is still quite impressive. Readers are exposed to sf/f/h stories throughout the year in various venues, including print magazines, online magazines, as well as a steady stream of single-author collections and multi-author anthologies that are published annually. Trying to read each and every story is like drinking water from a fire hose. So what is a short fiction lover to do?

One common approach is to let someone else cull the best stories of the year for you. This is exactly what several professional speculative fiction anthology editors do. They read massive amounts of stories every year, picking the best ones for their annual "Year's Best" anthologies. I spoke with the following anthology editors to get an idea of what goes into making a Year's Best speculative fiction anthology:

o Ellen Datlow, who co-edited (with Terri Windling, Kelly Link and Gavin J. Grant) The Year’s Best Fantasy and Horror for 21 years and is now editing The Best Horror of the Year. Her latest volume, The Best Horror of the Year, Volume 7, is out this summer.

o Paula Guran, who edits two separate Year's Best annuals, both publishing soon: The Year’s Best Dark Fantasy & Horror: 2015 and The Year’s Best Science & Fantasy Novellas: 2015.

o Rich Horton, who edits The Year's Best Science Fiction & Fantasy series that began in 2010. The 2015 Edition is new this month.

o Jonathan Strahan, who edits The Best Science Fiction and Fantasy of the Year, now offering its ninth annual volume.

Here's what they said when I asked them about their editing processes....

Q: How many short fiction stories do you read each year and in what publishing venues do you find them?

Ellen Datlow: Hundreds. I can estimate this by the number of stories I put on my annual recommended list—in 2014 [it was] 622, which means I read or skimmed at least five times that number.

Paula Guran: I really couldn’t count! And in addition to fully reading stories, there are some you read only part of. Then there is re-reading stories to make decisions. I also am looking for science-fiction and fantasy novellas now, too, so that adds to the reading. Not as many, of course, but still enough I don’t keep count.

Rich Horton: When I was obsessively counting stories, the totals reached around 2,400 per year. (That's gone down somewhat in the past couple of years.) I try to find them in as wide a variety of places as I can: all the conventional SF sources (print and online magazines, original anthologies, original stories in collections), but also certain non-SF venues that are fairly hospitable to the SF and Fantasy: the New Yorker, Tin House, Harper's, Granta, Zoetrope are all places where I've found cool stuff. Chapbooks are another good source, especially for novellas. Occasionally even newspapers. SF is particularly fortunate to have a history of tiny, at first glance unimpressive, 'zines that feature very good stuff, perhaps most notably Lady Churchill's Rosebud Wristlet and Not One of Us.

Jonathan Strahan: When you read a lot of short fiction over a fairly long period of time you begin to become more skilled at it, to develop a sense of when a story is or isn’t working, and when to abandon it. That allows you to look at a lot more stories than you actually finish reading.

To give you a number, I would say that I would look at about 2,500 stories per year, and would read about 1,000 of those. And of that 1,000, I would read half very closely, and then winnow down to a group that I read several times as I make my selections.

As to venues, I look at all of the main genre publishing venues, both in print and online. Publications like Asimov’s, Analog, F&SF, Tor.com, Clarkesworld, Lightspeed etc. are automatic. I probably have between 30 and 40 publications that I follow very closely. I also try to keep an eye out for any anthologies that are published, short story collections, single story publications as e-books, as well as mainstream publications like Tin House, The New Yorker, Conjunctions and so on.

Probably the biggest challenge these last few years has been finding more about where I can find short stories in translation. I’m eager to find work published outside the usual venues, and outside the U.K./U.S.

Q: Besides quality, what other criteria merit a story being included in a YEAR'S BEST volume?

Ellen Datlow: It needs to be what I consider horror, that is dark and disturbing. Obviously it's my taste that informs my year's best. I try to include a variety of types of stories—different voices/time periods/locations—but basically they're the stories that hit me the right way.

Paula Guran: The Year’s Best Dark Fantasy & Horror has a really broad range so, to an extent, I look for some variety. For The Year’s Best Science Fiction & Fantasy Novellas, I’m trying to find science fiction or fantasy that doesn’t overlap with the other volume, so I try not to go too dark. Still that doesn’t rule the darker novellas completely out.

Rich Horton: The things that impact story selection besides quality are: contractual availability (every year, we can't use one or two stories because of contractual hang-ups); length (usually I can only use a couple of novellas per volume); balance (I try not to use too many stories from the same source, I try to have a rough balance between SF and Fantasy, a story might be knocked out if another story too similar in theme/subject matter is already included). Sometimes novelty can be a tiebreaker...a new writer, or a story on a particularly unusual theme, might get the nod when I'm trying to choose between the last 10 stories for the last five spots. One other factor is cooperation with the other books we publish at Prime: Paula Guran and I sometimes want the same stories for our books, and so we negotiate a bit, not wishing to interfere with each other.

Jonathan Strahan: Quality is such a subjective thing that I’m a little reluctant to just skip over it, but setting any assessment of quality to one side, there are some considerations I take into account.

Still, I guess I’m looking for a few things. The first is genre. I edit The Best Science Fiction and Fantasy of the Year. I want stories that are clearly genre, or that comment on genre somehow. A goodly portion of the stories must be either core SF or core fantasy, and then I allow myself some room for stories that blur and blend genre to provide some counterpoint.

The second is rhythm. I’m very aware that someone is going to sit down and read the book I’m compiling. I want it to be an engaging and rewarding experience, so I’m looking for stories that have a variety of pacing to them, so I can piece together a book that welcomes readers in, lets them know where they are, and then occasionally surprises them.

I’m also looking for stories that feel current to me. More and more, especially when it comes to SF, I find I’m struggling with a lot of stale and old-fashioned stories. This is 2015 and I want to be featuring stories that are the best SF of 2015, not a riff off something from 1945. That said, if there’s a fantastic 1945-type story, I’ll probably include it.

Finally, there’s length. I want variety in each book. I have about 200,000 words to play with and want about 30 stories in the final book. This latter number is just a rule of thumb, though, that has evolved over the past decade. My process is that when I’m reading for a best of the year I will make notes as the year goes by. I keep track of things like the subject or theme of stories, the genre I think they’re written in, the length of the stories and so on. As the year goes on I transfer this to a spreadsheet and being to build up a longest of stories that are tagged by genre, theme, and so on. My first cut list will run to about 400,000 words.

I’ll start to re-read stories about two months or so before I make my final selections. On re-read I’m looking for things like how well the story holds up, how well I remember it, and the tone of the story (how engaging or readable it is). Slowly I’ll drop stories that cover similar themes, remove duplication, and try to winnow out longer stories. This usually leaves me with about 50% more stories than I need. From there it’s how much I love them, and how well the book balances.

I am, of course, also aware of issues like gender, race and nationality when I compile a book. I try to keep track of it as best I can, and to ensure that there is a variety of points of view in the stories I select. I want the book to be approachable to as many readers as possible, and that means including as many points of views as possible. While this was a real issue for me for a while, I made an effort over time to make reading more widely my own default, and as a result this has begun to take care of itself (though I’m always working at this). The selection processes I’ve outlined above tend to produce fairly diverse results now. Not always, though, and there are times where I deliberately choose the more diverse story over the less diverse story to achieve a satisfactory balance to a book.

Q: Does your YEAR'S BEST anthology tend to include one flavor or type of story over another?

Ellen Datlow: I hope it does the opposite. I include supernatural horror, psychological horror, the occasional sf/horror story, and terror tales.

Paula Guran: Definitely not for The Year’s Best Dark Fantasy & Horror. As I said above, I’m intentionally covering a lot of territory. And I have eclectic taste. Same thing with The Year’s Best Science Fiction & Fantasy Novellas, really, except for preferring less dark over dark dark.

Rich Horton: The one thing I try to do is feature stories from out of the way places if possible, and to feature stories from close to the edge of the genre (as well as of course some from smack dab in the middle!)

Jonathan Strahan: Not that I’m aware of. I try to balance between genres, I like stories with definite action in them, and I try to opt for a group of stories that are in a sense core Science Fiction or Fantasy to my eye. Other than that, someone else would have to read the books to see if there’s a flavor to them.

Q: What's the biggest challenge in producing a yearly YEAR'S BEST anthology?

Ellen Datlow: Not burning out by the time my reading period is over. Every year around January or February, I have the feeling that I never want to read another short story, I never want to write another summary of the year. And every year (so far) I get over that hump and start the next one.

Paula Guran: Getting it done. Time two!

Rich Horton: Well, that is a lot of stories to read in a year—it's not that I mind reading the stories, but I do feel like I miss some great novels because I run out of time. In a lesser sense, as the years go by it's harder to find something new to say in my introductions—I remain gobsmacked by Gardner Dozois' massive intros year after year.

Jonathan Strahan: Finding stories, without a doubt. There are all sorts of time management issues, and issues to do with contracting stories, getting permissions and so on. And it’s obvious that any one person trying to read all of the stories published has an enormous challenge in front of them (no one does it, but you try). But the biggest challenge is that short stories can appear anywhere these days. They’re used for promotional purposes and are as likely to be in a genre magazine as a stand-alone e-book to some website you’ve never heard of. It takes a lot of time, and it’s very easy to miss seeing them. That said, it’s always exciting when you find a new writer or a new story in some odd publication you’d never heard of before.

John DeNardo is the editor of SF Signal, the Hugo Award-winning group science-fiction and fantasy blog featuring news, reviews and interviews. You can follow him on Twitter as @sfsignal.