This review process, which needed to be completed no later than six months prior to the end date of the initial contract, was facilitated with the full council by independent human resources consultant Greg Tims.
Mayor Steve Chadwick said Williams' performance had been exemplary as the organisation responded to the direction set by elected members in the Rotorua 2030 vision.
"There has been considerable change in our community since 2013 and Geoff has led our organisation to both support and encourage growth in the Rotorua district.
"In 2013 we were responding to a district in decline and remarkably, now we have pressures of growth to navigate with our population now at 71,700," the mayor said.
"Strategies and visions are nothing if they can't be activated and Geoff has the councillors' confidence in leading the organisation to work differently with partners and community stakeholders for our district's advancement and this approach needs to continue."
Chadwick said highlights of Williams' tenure to date included a new financial strategy, organisational realignment to support Rotorua 2030, portfolios, the partnership with Te Arawa through the Te Tatau o Te Arawa board, Rotoiti/Rotoma Sewerage project, the Rotorua Wastewater Treatment Plant project and the 2030 vision refresh (The Rotorua Way) post the 2016 election.
"This has all happened against the need to continue to shape our district and organisation," Chadwick said.
"It's important that we continue to take advantage of the opportunities ahead for Rotorua while balancing the ongoing needs of our community. The next two years will continue to be challenging and the continuity of having Geoff leading the organisation was an important consideration and decision for all of our elected members."