As part of their research, Hounshell and Smith conducted sixty-one oral history interviews with forty-seven current and former chemical engineers involved in DuPont's R & D programs. Most of the pioneers had already passed away, but Hounshell and Smith were able to interview many individuals who had started as their assistants or had personal recollections of them. The Hounshell-Smith interviews constitute an exhaustive first-person account of DuPont's research programs with special emphasis on personalities and the organizational culture of the various DuPont research facilities. There is some discussion of the relative merits of the chemical engineering programs at several universities and of the research efforts of DuPont's corporate allies and competitors.