In 1977-78 Robert Freitas created the concept sentience quotient (SQ) as a way to describe the information processing rate in living organisms or computers. Freitas is authoring the multi-volume text Nanomedicine, the first book-length technical discussion of the potential medical applications of hypothetical molecular nanotechnology and medical nanorobotics. Volume I was published in October 1999 by Landes Bioscience while Freitas was a Research Fellow at the Institute for Molecular Manufacturing . He published Volume IIA in October 2003 with Landes Bioscience while serving as a research scientist at Zyvex Corp., a nanotechnology company headquartered in Richardson, Texas, during 2000-2004.
Also in 2004, Robert Freitas and Ralph Merkle coauthored and published Kinematic Self-Replicating Machines, the first complete survey of the field of physical and hypothetical self-replicating machines. In 2006, Freitas and Merkle co-founded the Nanofactory Collaboration, a research program to develop the first working diamondoid nanofactory.