He was elected president at the local authority group’s annual general meeting in Stamford, Lincolnshire, earlier this month.
At the meeting, Seddon said: "My aim for the year is to focus on how effective we are being as POS and how we best ensure that we are relevant and representative of our members and the country."
A chartered town planner with over 25 years’ experience at councils in the North West and East Midlands, Seddon becomes the 22nd POS president since the group's formation in 1997.
He is also chair of the Core Cities’ chief planners group and is the POS place making and heritage specialist.
The new senior vice-president is Sarah Platts, strategic planning and infrastructure manager at Kent County Council.