Kathmandu chief executive Xavier Simonet has resigned after five and a half years at the company.
Simonet, who intends working out a six-month notice period, is leaving to take up a senior role with the Australian Public Service.
"We are disappointed to lose Xavier," Kathmandu chairman David Kirk said. "We wish him well in the important work he will undertake."
Simonet led Kathmandu Holdings through a period of growth and re-positioning of the company, Kirk added.