California's insurability crisis provided the inspiration for the winner of this year's Climate and sustainability collaboration of the year.

Insurers had been fleeing wildfire-prone areas of the state as they were unable to provide cover at profitable rates.

Sustainability advocacy organisation Ceres and the California Department of Insurance both understood the solution to this problem – which is being mirrored in markets worldwide – required unprecedented collaboration that crossed traditional boundaries.

The two organisations joined forces to host the first Global Sustainability Insurance Summit (GSIS) in April 2024, creating a vehicle for bringing together the diverse expertise needed to address these complex challenges.

More than 200 stakeholders attended – including re/insurers, supervisors, academics, UN agencies and civil society organisations – to create what the organisers describe as "the most comprehensive climate insurance dialogue platform globally".

The success of that first event led to the GSIS returning in May 2025. Through these main events and ongoing collaborations and conventions, the GSIS is evolving to become a global laboratory for climate risk innovation.

InsuranceERM's judging panel was full of plaudits for the event. "A very significant undertaking to bring in this many renowned figures," said one. "A genuine collaborative approach across a wide range of sustainable insurance needs – sharing of best practice leading to better outcomes for all," said another.