A method for estimating the quality of a call in which a first user terminal (102) is an end point, the method comprising: establishing an end-to-end connection between the first user terminal (102) and a node related to a callee, the end-to-end connection via an access point of a network by which the first user terminal (102) is connected to the network; displaying information, at the first user terminal (102), indicative of an expected quality of a call in which the first user terminal (102) is the end point, in dependence on information indicative of the quality of the end-to-end connection; and providing call initiation means at the first user terminal (102) for enabling a user of the first user terminal (102) to then selectively establish a call between the first user terminal (102) and the callee, the method characterised in that the information indicative of the quality of the end-to-end connection between the first user terminal (102) and the node related to the callee is determined using a method that comprises: determining a transmission time for each of a plurality of packets in a queue received at the first user terminal (102), based on information received with the packets; determining a reception time for each of the plurality of packets; receiving, at an estimation function, successive sets of observations including in each set of observations transmission time, reception time and packet size; and determining the information indicative of the quality of the end-to-end connection by using a relationship between the information indicative of the quality of the end-to-end connection, an amount of data in the queue, packet size, and an interval between packet transmissions. establishing an end-to-end connection between the first user terminal (102) and a node related to a callee, the end-to-end connection via an access point of a network by which the first user terminal (102) is connected to the network; displaying information, at the first user terminal (102), indicative of an expected quality of a call in which the first user terminal (102) is the end point, in dependence on information indicative of the quality of the end-to-end connection; and providing call initiation means at the first user terminal (102) for enabling a user of the first user terminal (102) to then selectively establish a call between the first user terminal (102) and the callee, the method characterised in that the information indicative of the quality of the end-to-end connection between the first user terminal (102) and the node related to the callee is determined using a method that comprises: determining a transmission time for each of a plurality of packets in a queue received at the first user terminal (102), based on information received with the packets; determining a reception time for each of the plurality of packets; receiving, at an estimation function, successive sets of observations including in each set of observations transmission time, reception time and packet size; and determining the information indicative of the quality of the end-to-end connection by using a relationship between the information indicative of the quality of the end-to-end connection, an amount of data in the queue, packet size, and an interval between packet transmissions. determining a transmission time for each of a plurality of packets in a queue received at the first user terminal (102), based on information received with the packets; determining a reception time for each of the plurality of packets; receiving, at an estimation function, successive sets of observations including in each set of observations transmission time, reception time and packet size; and determining the information indicative of the quality of the end-to-end connection by using a relationship between the information indicative of the quality of the end-to-end connection, an amount of data in the queue, packet size, and an interval between packet transmissions.