Victoria Police commissioner Graham Ashton has returned to his post after taking six weeks leave due to fatigue-related illness.
The chief commissioner announced in November he was "run down, both physically and mentally" and needed three to six weeks off duty.
Victoria Police staff welcomed back their leader on Monday and he praised the force for their efforts over the festive period.
With Victoria Police placing a greater emphasis on mental health, Mr Ashton at the time said it was critical he set a good example and seek to address his condition.
"I have been heartened to see this increasingly occurring across the force," the chief commissioner, in his mid-50s, said in a statement.
"It is important that I therefore walk the talk, and now take the necessary time to deal with my fatigue issues."
During his absence, deputy commissioners Andrew Crisp and Shane Patton have managed major incidents including the Flinders Street attack and African youth crime furore.
Mr Ashton has been Victoria's chief commissioner for two-and-a-half-years since replacing Ken Lay.
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