The Laboratory of Thermal Turbomachines (LTT) at the National Technical University of Athens (NTUA) was founded in 1982. It has a substantial and modern infrastructure in a number of turbomachinery related research areas. It hosts a strong research group that works under contract and/or in collaboration for contract work with industrial outfits and organizations. Extensive research in the field of gas turbine performance modelling and diagnostics has resulted in comprehensive engine models for a large variety of engine configurations and the establishment of new diagnostic methods. Techniques for engine condition assessment and fault diagnosis have been developed and diagnostic systems have been produced and are currently installed in gas turbines operating in the field. Several CFD techniques have been developed for the analysis of internal and external flows, i.e. turbomachinery cascades, aircraft wings, etc. and, also, the development of powerful stochastic and deterministic methods based on evolutionary algorithms and adjoint approaches, respectively, have resulted to the shape optimization of various aerodynamic bodies. Being part of a higher education institution, LTT supports a number of undergraduate and postgraduate courses and continually transfers the knowledge gained from research to educational activities.