A joint Euratom-CEA, Euratom-FOM electron cyclotron resonance heating (ECRH) programme was conducted on the TFR tokamak during 1985 and 1986, with 600 kW of ECR power at 60 GHz. The paper describes the experiments performed during this period and analyses the results. In spite of considerable electron heating, a degradation of the global energy confinement time has been observed in all cases, with incremental confinement times ranging from 1 to 2 ms, depending on the experimental conditions. The electron thermal conductivity has been determined in three different independent ways and the results are in reasonable agreement, but only 1/4-1/3 of the gyrotron power is found in the rate of change of the plasma energy. Other topics addressed are: impurity content and transport, sawtooth behaviour, MHD stabilization, suprathermal electron population and pellet ablation during ECRH.