A couple of good questions came in response to my description yesterday of the Raymonda tutu build going on right now. This is from Seth:
"I know this may sound like a stupid question to you, but if the costumes are essentially specially made for each dancer, does this mean that new costumes are always being made? How do they or can they get customized from year to year (or are they taken apart to be used for new costumes)? And, if they're made well in advance, is there a concern for weight gain/loss of the dancer (or is that even a consideration) - do you (and the other dancers) have a strict diet that you're to follow?"
Nope, those aren't stupid questions! They're completely logical things to wonder and are real issues that have to be dealt with.
First of all, even though costumes are originally made for a specific dancer, they are also made with the knowledge that they will not only have to last a really long time and take a lot of abuse, but will have to sooner or later be worn by other dancers who may or may not be a similar size. So, they are always built with places and ways to make alterations. Some costumes are easier to alter than others, and there is only so much room for adjustment, so in come cases it is indeed impossible to fit another dancer into a certain costume. When that happens, some solution will be found-- another costume will be made, borrowed, or pulled from a different ballet. Tutus are harder to make significant alterations to than, say, a spandex tunic or a loose flowing dress.
Another thing to keep in mind is that when a set of costumes is made for the corps de ballet of any particular piece that we know is going to be performed over and over again (for example, Waltz of the Flowers in Nutcracker), they are made deliberately to fit many dancers easily. (There are so many casts of Flowers over the years and throughout the run that several women end up wearing the same costume at some point). Those costumes are made with several rows of hooks and eyes in the back, elastic shoulder straps that are easy to adjust, and elastic tabs with buttonholes inside the waistband that are attached to the dancer's trunks underneath (hard to explain, but it's an ingenious system). This way, dancers of a pretty big range of heights can wear the same costume. And the long billowy tutu skirt has a way of evening out small height differences.
Another trick often used with classical tutus is to construct them so that the bodice is separate from the skirt. This is what we do for Nutcracker's Sugarplum Fairy tutu. For example, I might wear the same skirt as another Sugarplum, but a different bodice. So the two pieces are separated after each performance and reattached to the correct top or bottom for the next dancer to perform.
It's not too common for a dancer to "outgrow" a costume between the time it's made and the time they are to perform, or vice versa. Occasionally, if the ballet is an especially challenging one and the rehearsal period is quite demanding, you'll go to put your costume on for dress rehearsal and find that it's a bit looser than it was a few weeks previously, but that's likely to be a minor adjustment that's easy for wardrobe to make. Again, even given how perfectly the costumes are made to fit us, they are also forgiving in terms of stretch fabrics (used more and more commonly these days) and adjustable backs, shoulder straps and waistbands. The wardrobe people are pure genius when it comes to "tweaking" a costume to make it feel comfortable and look great!