Focus Network publishes 20 magazines including Cycling Weekly, VolksWorld, SuperBike Magazine and Park Home & Holiday Caravan from its offices in Croydon.
Clarkson moves to Country & Leisure from IPC Connect, where he spent three years as publisher of Chat and Chat Specials, and most recently as the launch publisher of Connect's new real-life weekly Pick Me Up.
Clarkson joined IPC in 1995, working in advertising across Family Circle, Essentials and Woman & Home, and later in the women's weeklies portfolio. He then went on to work at Haymarket in 2000 and rejoined IPC in 2002 to work within IPC Connect.
He will also join the IPC Country & Leisure board, reporting directly to managing director Paul Williams, and will take up his new role on May 3.
Williams said: "Niall's excellent publishing and commercial experience, together with the real passion he has for specialist magazines, will be invaluable in developing the group's wide-ranging portfolio."
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