A system for determining the number and the identity of users in a vehicle, comprising - at least one vehicle with an associated individual vehicle ID (F-ID) and with a vehicle module for the wireless transmission of vehicle-specific position and time data (F-OZ) to the system, - at least one mobile telecommunications network with a network server and several mobile terminals (11, 11 a, 11 b, 11c), suitable for communication at least in the mobile telecommunications network, whereby individual terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) are associated with each of the mobile terminals (11, 11 a, 11 b, 11c), and the users (1, 1 a, 1 b, 1 c) of the mobile terminals (11, 11 a, 11b, 11c) can be identified on the basis of the terminal ID (T-ID, T-ID1, T-ID2, T-ID3), and the network server is configured to transmit terminal-specific position and time data (T-OZ) to the system, - one or more data storage units for storing the vehicle-specific position and time data (F-OZ), together with the vehicle ID (F-ID), in order to ascertain the individual travel route of the at least one vehicle, and in order to store the terminal-specific position and time data (T-OZ), together with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) and also personal data of the users (1, 1a, 1b, 1c) associated with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) in order to ascertain individual person-specific movement routes (TR, TR1, TR2, TR3) for each of the mobile terminals (11, 11 a, 11 b, 11c), - an analysis server that is configured to access the one or more data storage units and to compare the ascertained individual travel route to the ascertained individual movement routes (TR, TR1, TR2, TR3, TR4), and, in case of sufficient correspondence (U-FT) of at least one of the individual travel routes with one or more of the individual movement routes (TR, TR1, TR2, TR3, TR4), at least over a given time interval, to link the appertaining vehicle ID (F-ID) with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) belonging to these individual movement routes (TR, TR1, TR2, TR3, TR4), and to store this in the data storage unit or units, together with the personal data of the users (1, 1a, 1b, 1c) associated with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3), whereby the correspondence is only sufficient (U-FT) if the degree of correspondence is above a defined threshold value and, when it comes to ascertaining the degree of correspondence, the time and position correspondence of the starting and ending points (SP, EP) of the individual travel route and the individual movement routes (TR, TR1, TR2, TR3, TR4) that are to be compared to it are given a higher weighting than points (P1, P2, P3) of the travel and movement routes (FR, TR) between the starting and ending points (SP, EP). - at least one vehicle with an associated individual vehicle ID (F-ID) and with a vehicle module for the wireless transmission of vehicle-specific position and time data (F-OZ) to the system, - at least one mobile telecommunications network with a network server and several mobile terminals (11, 11 a, 11 b, 11c), suitable for communication at least in the mobile telecommunications network, whereby individual terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) are associated with each of the mobile terminals (11, 11 a, 11 b, 11c), and the users (1, 1 a, 1 b, 1 c) of the mobile terminals (11, 11 a, 11b, 11c) can be identified on the basis of the terminal ID (T-ID, T-ID1, T-ID2, T-ID3), and the network server is configured to transmit terminal-specific position and time data (T-OZ) to the system, - one or more data storage units for storing the vehicle-specific position and time data (F-OZ), together with the vehicle ID (F-ID), in order to ascertain the individual travel route of the at least one vehicle, and in order to store the terminal-specific position and time data (T-OZ), together with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) and also personal data of the users (1, 1a, 1b, 1c) associated with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) in order to ascertain individual person-specific movement routes (TR, TR1, TR2, TR3) for each of the mobile terminals (11, 11 a, 11 b, 11c), - an analysis server that is configured to access the one or more data storage units and to compare the ascertained individual travel route to the ascertained individual movement routes (TR, TR1, TR2, TR3, TR4), and, in case of sufficient correspondence (U-FT) of at least one of the individual travel routes with one or more of the individual movement routes (TR, TR1, TR2, TR3, TR4), at least over a given time interval, to link the appertaining vehicle ID (F-ID) with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3) belonging to these individual movement routes (TR, TR1, TR2, TR3, TR4), and to store this in the data storage unit or units, together with the personal data of the users (1, 1a, 1b, 1c) associated with the terminal IDs (T-ID, T-ID1, T-ID2, T-ID3),