This Interview has been provided by Orbit, and is printed with their permission.

September sees the publication of Tad Williams' MOUNTAIN OF BLACK GLASS, the third volume of his breathtaking Otherland series following CITY OF GOLDEN SHADOW and RIVER OF BLUE FIRE - both of which are available in paperback. We asked Tad about the serious business of series.

To what extent did you have the Otherland series planned out before you started writing the first volume?
I tend to go at my multi-volume works in the same way I would approach single-volume novels - they're just longer, is all - so I have a pretty good idea of how the thing's going to work before I begin. That doesn't mean I know everything, not by any means. But I have a grasp of the overall structure - the volumes are being written as sections of the whole, not just as individual books.

How many volumes are there going to be in the series, and do you know how it's going to end?
Four volumes in total, and yes, most definitely. I've known the most important bits of the ending since before I started - crucial when you're handling as many tricky and mysterious plot-lines as these books contain. You can't foreshadow if you don't know what it is you're foreshadowing ...

Otherland is the second multi-volume series you've written. How different do you find the writing of each book as a series progresses?
In some ways, each successive book veers farther from the original plan, because of the sheer complexity, the quantum branching of every little decision. However, that makes the challenge of bringing it all together successfully even more interesting.

Do you think of Otherland as a single novel split into parts, or separate novels?
I think of Otherland as a single story, divided largely out of necessity. However, I try to give each volume at least some individual shape, so as not to frustrate readers completely. In practice, this means trying to come up with three internal `milestones' of some kind that will allow a volume to feel like it has an ending.

What do you think makes a huge series such as Otherland appeal to SF and fantasy readers?
I think one of the nice things about Otherland is that it has something to offer both SF and fantasy readers - the rigour of SF, the fact that things have explanations other than `magic', the attempt to deal realistically with the near-future, and for fantasy fans, the sheer scope, the monsters, the wild settings, all the normal stuff that makes fantasy fun and frightening.

Do you have any ideas what you're going to write after Otherland? Another series?
My current plan is to do a single-volume (although probably a pretty LONG single-volume) fantasy novel, with the tentative (VERY tentative) working title of either ORPHAN or LAST TRAIN TO FAIRYLAND. I also plan to do a collection of short stories set in different historical periods of Osten Ard, the setting for the Memory, Sorrow and Thorn books. And I'm contemplating some other possibilities as well.