IHis research interests include cationic host defence (antimicrobial) peptides as novel antimicrobials, anti-biofilm agents and modulators of innate immunity, the development of alternatives to antibiotics for resistant infections, the systems biology of innate immunity, inflammatory diseases and Pseudomonas aeruginosa, and antibiotic resistance, particularly multidrug adaptive resistance. He has published more than 800 papers and reviews, is an ISI highly cited author in Microbiology with more than 113,000 citations and an h-index of 168, and has 72 patents awarded.