Rich in themes and ideas
Besides the genetic aspects of the story, Kress mixes in not a small amount of economic philosophy. Leisha's father is a proponent of a philosophy called Yagaism, which holds that the only moral way to live is by each individual producing what they do best and trading it to others. The symbol of this approach is the contract, representing the free exchange of goods and services. The name of the novella, Beggars in Spain, is actually a reference not to genetics but to an argument against this theory, and much of the story involves Leisha's internal struggle to embrace both the individual achievement demanded by Yagaism as well as the incorporation of compassion for the less fortunate (as represented by the Beggars in Spain analogy).

In addition, the author manages to build rich characters by showing their interpersonal struggles. Leisha has a sister who is "normal" and openly ignored by their father, causing severe conflict between the two sisters. Leisha herself comes into conflict with her father later in her life, and she even has several heated exchanges with some of the other Sleepless.

Indeed, it is Kress's ability to merge these various themes of genetic engineering, personal struggles, and economic philosophy that make this such a great novella. Kress comments in her interview that she prefers the novella form. A novella is defined as a short work of between 17,500 and 40,000 words. Beggars in Spain is about 25,000 words, or about one third the length of a typical novel. She says that this length of story gives the author enough room to build compelling characters but is short enough not to require multiple subplots that are typical of novels. Thus, the drama can remain on target and concentrated.

Although the novella is great, and a landmark of sorts, that's not to say it's perfect. For instance, some of Kress's extrapolations of the benefits of Sleeplessness seem to be a stretch. It's also hard to believe there aren't any negative side effects to the extensive genetic modification and manipulation of all manner of hormones necessary to remove the need for sleep, as proposed in the story. However, I would consider these to be minor points, small flaws in an otherwise very precious gemstone. I am willing to suspend my disbelief for the greater ideals and goals of the storyline.

If you're looking for a novella-length work to give you a few hours of pleasurable reading, and if you're a fan of the grand ideas science fiction can often provide, this one is strongly recommended.

Other Kress shorts
Fictionwise.com is also providing a bundle of four Kress genetics stories that includes Beggars in Spain. You may also buy the other three stories ala cart. Here are short reviews of each, in order of how much I liked them:

Evolution
This short story shows us a world in which antibiotic-resistant bacteria has run amok in hospitals, causing terrorist activity directed against doctors who abuse antibiotics. The plot is fast-paced and the characters richly developed. Given that some forms of tuberculosis are already highly resistant, we may actually face the grim future portrayed here, but the story, in general, is not a downer. After Beggars in Spain, this was my second favorite of the four stories in this bundle. It has a length of 9,400 words, and is priced at $1.19.