From the back cover:
We can improve you.
We have the technology...
Take the next step in human evolution. With cybernetics, you can advance in ways nature never intended. Cyborgs are the people of the future, and the world of tomorrow is theirs for the taking -- a world of virtually limitless possibilities! d20 Cyberspace contains everything you need to build cybernetically enhanced heroes and virtual realities, as well as rules for including cybernetics in a modern, near-future, or far-future campaign.
To use this product, you also need the d20 MODERN Roleplaying Game core rulebook and the d20 Future supplement. This product is compatible with other d20 System roleplaying games.