The annual event, hosted by HR magazine at a prestigious event at Claridges, names the most influential practitioners and thinkers (both UK and international) in HR.
For the first time this year there was a readers' choice category, in which HR magazine readers voted for the HR director they feel has made the biggest contribution to the industry.
The ranking is sponsored by HR and payroll company Ceridian and Open University Business School, with help from research partners Ashridge Business School.
Most Influential Practitioners
Royles, recently appointed director of HR and organisational development at Leeds Teaching Hospital NHS Trust, took first place in the ranking ahead of Penguin Random House group HR director Neil Morrison (second) and new BBC HR director Valerie Hughes-D'Aeth (third).
HR magazine publisher Sian Harrington called Royles the "most high-profile HR professional in the country" when announcing his top placing.
Royles said he was "delighted" to be the first person from the public sector to win the award three times.
"Working in an organisation like the NHS I've always tried to be thoughtful in my approach while in a difficult climate and with people who are doing invaluable work every day," he said.
Most Influential UK Thinker
Cary Cooper, distinguished professor of organisational psychology and health, Lancaster University Management School, took the top spot in the most influential UK thinker category.
CIPD chief executive Peter Cheese was next on the list, with Bath University School of Management professor of organisational psychology Rob Briner named in third.
Cooper said the recognition was "wonderful for all the people who work in wellbeing".
"How we treat people in the workplace is so fundamental," he said. "It's important to recognised that employment goes well beyond remuneration."
Most Influential International Thinker
In the top international thinker category Sylvia Ann Hewlett, founder and CEO of US-based Center for Talent Innovation, fought off two Harvard Business School professors to take first place.
Konosuke Matsushita professor of leadership, emeritus, John Kotter was placed second, with Ernest L Arbuckle professor of business administration Rosabeth Moss Kanter in third.
Dorchester Collection VP, people & organisational development, Eugenio Pirri was named the inaugural winner of the readers' choice award. IMI group HR director Geoff Tranfield came second, with Marks & Spencer HR director Tanith Dodge completing the top three.
Pirri said he was "delighted" to be selected by his peers.
"Since I moved to this country around eight years ago I've always seen these list and aspired to be on them, so this is a great honour," he said.
You can now explore the full HR Most Influential rankings in a dedicated section of the HR magazine website. You'll find profiles of all the people on the lists, as well as full sector lists.
Look out for coverage of HRMI in the October issue of HR magazine, and a dedicated supplement coming with the November issue.