In March, Chemistry, part of TheNetworkOne group, acquired new-media agency PDG Graphics and IT events and publishing company Bearpark for an undisclosed amount.
In January, it launched Chemistry Consulting, a specialist consulting arm, offering CRM strategy development.
Foo said: "My focus will be on continuing our success in new business and reputation, while also increasing the agency's profile."
Foo was previously client services director, which will now be divided into two roles, with an announcement on the appointments expected later this month.
Diane Charlton, managing director of Chemistry, will now focus on the integration the agencies three divisions; Chemistry London, Bearpark and the Nottingham-based Chemistry Digital.
The agency's accounts include Yell, Diageo, Unilever, Transport for London, Kodak, Toshiba and Experian.
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .