Tariff Consultancy Ltd was founded by Margrit Sessions who previously headed up the research company Tarifica/PBI in 2006. Tariff Consultancy Ltd (TCL) is an international telecoms research and consultancy firm based in London. The basis of TCL’s research is a unique database which assembles pricing data from Data Centre companies across Europe, Asia-Pac, Middle East, Africa and North America which is used as basis of both reports and subscriber services. Its flagship product is the Data Centre in Europe report published annually.