Based in Bucharest, Business Travel Turism provides corporate events and incentives and was recently recognised by the Hotel Tourism Leisure Investment Conference as the best events business in Romania.
ATPI Group now has a network of offices and partners in 42 countries including Taiwan, Vietnam, Japan, Brazil and Finland.
Graham Ramsey, chief executive officer, ATPI Group, said: "We look for regional expertise and excellence in our partners and are very pleased to add Business Travel Turism to our growing network.
"Expanding our Group operation via acquisitions and new partners is a key part of our growth plans. We look forward to the opportunities that this new partnership brings to both businesses."
Paula Dobrescu, owner and CEO, Business Travel Turism, added: "The central European region is experiencing a fast pace of growth, and our economy is outperforming much of northern and western Europe.
"Our business has grown significantly in Romania thanks to a developing local market, and we are excited about the potential that our partnership with the global ATPI Group brings as we strengthen our position as the travel management company of choice in central Europe."