At this point in history, we are all digital photographers. Whether we shoot film and have it scanned or capture direct to digital, almost all images will be judged and/or manipulated on computer monitors in their production cycle. Unfortunately, there is still a lot of confusion about proper color management and your images stand a good chance of being edited on a out-of-date or improperly calibrated monitors and will often be converted or tagged with incorrect color spaces. The only real protection you have as a photographer is to properly color manage using industry standards. A good place to look for standards is http://www.updig.org. They have set up some guidelines for how digital images should be viewed, delivered and printed. These guidelines still leave some room for interpretation so based on my experience working with top photographers and from delivering digital files to ad agencies and magazines, I can offer a more specific answer.

Hardware calibrate your monitor to a White Point of 6500K, Gamma 2.2, & Luminance 120 cd/m2 and choose Adobe RGB 1998 as your color space in Photoshop. Yes, ProPhoto RGB is a larger color space that can be used to manipulate a greater range of colors but you can't see those colors on today's monitors and most output devices can't print that large of a gamut. Some inkjet printers can print a good portion of the ProPhoto RGB space but if you can't see what you are editing on screen, I question it's usefulness for everyday printing. Also keep in mind that a lot of today's digital printers like the LightJet, Frontier and Indigo press all print in sRGB color psace. This means that any gains you make from editing in ProPhoto RGB are thrown out when converted to sRGB.

Hardware calibrate your monitor to industry standards and your images will have the greatest chance of being viewed or printed consistently when sent outside of your control. Invest in a good calibration puck like the i1 Display or the new x-rite Colormunki. For a limited time, you can also trade in your old calibration puck for a credit towards a Colormunki.