Marinker will have a creative, strategic and business development role within Good Relations and will also seek to develop opportunities with other Bell Pottinger businesses.
The appointment follows a number of high profile consumer-related wins for the agency, including Nintento and comparethemarket.com.
Marinker joined CDR in 2004 to establish a consumer practice. Previously he was a director at Porter Novelli.
He said: ‘I had six very happy years at CDR and I am proud of what we achieved there but GR represents a new and exciting opportunity. The business is going great guns and there is an energy around the Bell Pottinger Group which I found irresistible.’