Prf. Holloway is a world authority on the genetics of Pseudomonas species important for their potential in industrial applications and for recombinant DNA research, He collaborated with ICI UK on genetic aspects of the "Pruteen" project and with ICI Australia on the use of Pseudomonas to degrade chlorinated hydrocarbons.

As Chairman of the Research Grants Advisory Committee/ National Biotechnology Programme, he has been guiding much of the industrially oriented biotechnology R&D in this country.

His pioneering work has been recognised both here and overseas and is reflected in numerous publications and in his election as Fellow of the Australian Academy of Science. He is a recipient of the J. Purkyne Medal of the Slovak Medical Society and wes awarded the Order of Australia in 1989.