Chromatic aberration, spherical aberration and astigmatism induce sweat on the brows of optical designers in many diverse application areas. Avoiding these deviations from "perfect" optical systems is often difficult, but correcting them with aspheres can be expensive or inappropriate. An increasingly interesting option is gradient-index optics. Their progressively changing refractive index can control photonics in ways that can improve performance and save money in a variety of photonics applications. Although they were once an optical curiosity, they are now included in the "catalogs" of major optical design software packages, and designers are increasingly interested in their capabilities. The change marks this technology's migration into the mainstream of photonics problem-solving.