Throughout Europe, there is currently a trend towards greater monitoring and improvement of the internal performance of public transport operations, in order to achieve a high quality service within the available resources. Transport operators have been looking for a mechanism to investigate and achieve quality refinement and optimal management standards, and benchmarking is perceived as able to play this role. Up to now, only a few benchmarking methods have been developed that are able to assess the internal quality (efficiency and competitiveness) of public transport operators. Therefore EQUIP has developed a series of comparison procedures, and has identified and tested the most suitable indicators to measure quality and the areas that could yield improvements in efficiency.