Updated January 17th, 2022: They are now an imprint of Hades Publications. Their facebook page is still very active, but I couldn’t see any books listed that were published in the last year. This could be because their website is not ideally organized. For example, the book they have listed as most recently published was published in 2015, but they have published many more since than.
Edge is an established and well respected Canadian publisher of Science Fiction and Fantasy. They have great distribution within Canada, and good distribution within North America. They are open to authors regardless of nationality.
Their website is a little outdated, there is a mention of floppy disks in their submission guidelines, but it is functional and up to date in terms of listing author readings, up coming books and events.
The books I have seen and read largely have excellent covers and are always well edited. They have an e-publishing imprint that encountered some management issues a few years back, but seems to be resolved now.
They favor authors without agents. They are only interested in publishing novel length Science Fiction and Fantasy for adults. Their list of preferences include books with depth and insight, original ideas, characters with believable behaviors, strong plots, unique settings and solid science or magic systems.
They only accept completed manuscripts that have been thoroughly edited. If you are not sure your manuscript fits within their standards please send a query letter first.
Otherwise, submit the first three chapters, prologue (optional), synopsis, cover letter, title page, and self addressed and stamped envelope. All submissions must be made through the mail. They do not allow simultaneous submissions. Response times vary, but an older report says that they are trying to respond to all submissions within four months.
To get a better sense for what they publish browse their storefront. To learn more you can read their extensive FAQ section.
If you are interested in submitting you should read their full submission guidelines here. They are extensive and detailed.