Chris Mallender has left his role as chief executive of Corby Council.
A statement from the authority said Mr Mallender, who has been on extended leave from the council since December, will take up a 11-month secondment working on a European Union alternative energy project from Monday.
In his time as chief executive, Mr Mallender has overseen a host of major regeneration projects including the Corby Cube, the Rockingham Triangle sports complex, Corby International Pool, Corby railway station, the new Tresham College campus and the Willow Place shopping centre.
Cllr Beattie said: “We would like to take this opportunity to thank Chris for his time, hard work and dedication to Corby and the council. We wish him all the best in his secondment and hope his new venture proves successful.”