The price of the acquisition was not stated.
Teneo described Credo, which employs 60 people, as a "highly-respected management consulting firm focused on corporate strategy, transaction services, commercial and operating model transformation and performance improvement".
Credo will report to Teneo’s Consulting division, with its six partners set to join the extended global leadership team.
Teneo has now completed four acquisitions in 2017, and Credo is the first outside the comms and public affairs sectors. The others are: Asian PR agency Ryan Communication, Brussels-based public affairs and strategic comms shop Cabinet DN, and US agency Fitzroy Communications.
US-based Teneo has made nine acquisitions since launching in 2011, most notably UK agency Blue Rubicon, now Teneo Blue Rubicon.
Declan Kelly, chairman and CEO of Teneo, said: "Today’s acquisition will help further the expansion of Teneo’s global management consulting capabilities in response to client demand.
"We are very pleased to welcome the Credo team to Teneo. They have a very strong reputation for delivering results for clients and will be a great addition as our business continues to grow."
Credo managing partner Simon Bones said: "This represents a tremendously exciting moment for our firm, our clients and our staff. The combination of Teneo’s and Credo’s world-class strategic advisory capabilities will create a truly differentiated proposition for our clients and an excellent platform for growth. We are delighted to be joining forces with Teneo."