In addition to his research in this country, Dr. Stalnaker worked for three years in Europe. His first European position was at the Institut fuer Rechtsmedizin at the University of Heidelberg, West Germany.  Under contracts with the German Automotive Manufacturers Association and Volvo of Sweden, his responsibilities were to extend their cadaver impact sled testing capability and to help run cadaver tests. While at the Institut fuer Rechtsmedizin, he studied autopsy techniques and assisted in over one hundred autopsies on trauma victims. This work was followed by a short stay at the Instituut voor Wegtransportmiddelen, (Research Institute for Road Vehicles) at TNO-Delft, The Netherlands. His responsibilities included conducting classes in Biomechanics and constructing data sets for crash victim simulation mathematical models. He then went to work at the Laboratoire de Physiologie et de Biomechanique of the Association Peugeot-Renault in La Garenne-Colombes, France. While at Peugeot-Renault, he redesigned the Part 572 dummy's thorax for use in lateral impacts.  In 1979 he returned to TNO-Delft, where he developed an instrumented dummy abdomen, a child restraint system design using computer simulation, and conducted many tests at the sled laboratory using dummies and cars. While in The Netherlands, representing the Dutch, he was very active in the European Economic Community (EEC) and International Standards Organization (ISO) committees that set standards for automobiles in Europe. He left TNO at the end of his contract, in the autumn of 1980, to take up a position at Southwest Research Institute (SWRI) in San Antonio, Texas. While at SWRI, he carried out experiments on neck injuries and the "out of position child problem" associated with airbags. He also worked extensively on Crash Victim Simulations, using the MADYMO program.

Dr. Stalnaker became an Associate Professor, at The Ohio State University, in the autumn of 1982. While at The Ohio State University, he taught courses in instrumentation and system dynamics, as well as a course in which his students designed, built, and raced a Formula Car.  In 1984, he was tenured. He continued his research in biomechanics, with emphasis on human tolerance, dummy development, and mathematical modeling. In 1994, he was appointed to the faculty of the Department of Biomedical Engineering at The Ohio State University. Along with these research programs, Dr. Stalnaker managed masters and Ph.D. students who worked on these projects and used this research towards their degree. He has continued his national and international biomechanics committee work.

In 1995 Dr. Stalnaker resigned from his position at The Ohio State University, continued as an adjunct professor in 1996 in both biomedical and biomechanical engineering. Dr. Stalnaker left The Ohio State University to devote full time to his company, Ristal Engineering, Inc., that was formed in 1983. Dr. Stalnaker has since been consulting in the areas of product liability as well as general research.