NSW Premier Gladys Berejiklian announced the new agency, Resilience NSW, and Mr Fitzsimmons' appointment on Monday, describing him as "one of the true heroes of NSW".

The premier said the new agency will be dedicated to "world-leading disaster preparedness and recovery" after the state endured a summer of drought, bushfires, flooding and now a COVID-19 outbreak.

Paying tribute to RFS staff and volunteers, Mr Fitzsimmons described his decision to step away from the RFS after 35 years as "deeply personal and difficult".

"I've been unashamedly extremely proud of the extraordinary work of the men and women of the Rural Fire Service both volunteer and salaried alike.

"Volunteerism, volunteering is critical to the culture of the RFS ... we truly value, appreciate, honour and respect the work of the men and women who give of themselves for want of nothing in return except to make a difference in their local community.

"And we saw them this season, along with their salary counterparts, day after day, week after week, month after month, stepping up with the relentless nature of this fire season, the relentless nature of the weather and the awful toll that was occasioned across the state, so it was a difficult decision.

"As I said in my message to the membership, the right decisions, the important decisions are often the most difficult and when you add longevity within an organisation, which is very much like an extended family - it was tough but it's the right thing to do."

Mr Fitzsimmons accepted the role, he said, to continue to make a "meaningful difference" in the lives and livelihoods of people, communities, business and industry.

"I genuinely believe that we can leverage off all of the existing resources of government, we can improve the way we manage and deliver services to the community of NSW.

"We've got a lot of people hurting across the state right now, as a result of all manner of challenges, disasters, drought, bushfires and of course the COVID-19 response and there is more to come in our future you can be guaranteed."

Seeing firsthand the devastating effects of the recent fire season, Mr Fitzsimmons said he is committed to assisting those that need help now or in the future.

"There is something very impactful, there is something quite overwhelming when you're visiting relief centres, when you're visiting recovery centres and people come up and want to give you a hug and are quite emotional because they have nothing left.

"They're looking to you, they're looking to the government to try to help get them through their grief-stricken set of circumstances.

"I look forward to being able to help those most in need right across NSW."

Mr Fitzsimmons acknowledged NSW faces many challenges.

"I have no doubt through the emergency management framework of this state we can do better, we can improve and get to those that need it most.

"Right now with those that are still working through the enormity of the drought, the bushfires and now COVID, there's a lot on our plate here and now and we know there's a lot in the coming months, weeks and years.

"It's not just about physical rebuilding, it's not just about getting our infrastructure and systems and essential services better going into the future, but it's also very much about the psychological and emotional wellbeing of all those individuals and the communities collectively.

"We know recovery is most effective when it's individually led, when it's community-led and there is already a great deal of extraordinary work going on across the state ... I am committed to making sure we amplify that and build on that going into the future."

Mr Fitzsimmons will depart from the RFS over the next month and begin his new role in May.

Mr Fitzsimmons said building resilience must start at the grassroots level.

"Building resilience in our local communities, our ability to withstand, prepare for and rebound after disruptions is really important."

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