"Those of us who have been fortunate enough to know or to be led on a tour by Troy have lost a dear friend.
"No words can adequately express our sadness over Troy's death and our condolences are passed onto his family in New Zealand. We will honor Troy's memory by continuing our efforts in YPT and to continue the work he loved so much."
In a 2018 interview with NK News, Collings said he had been fascinated with the country ever since he watched A State of Mind many years ago.
After visiting the North on a research trip he realised Pyongyang was serious about tourism and decided to start the firm to bring foreigners in.
"I saw the potential tourism had to help the locals and to influence the country's development," Collings said.
"More importantly, I made some real human connections with people I met that had a profound effect on me and I decided during that trip that this is what I wanted to dedicate my life to."
He helped open the Tumen-Namyang border crossing between China and North Korea to foreign tourists in 2012, and became the first westerner to cross the border.