The invention relates to temperature controlled short duration ablation with multiple electrodes. The invention discloses an apparatus including a catheter configured to be inserted into an organ of ahuman body. A plurality of electrodes are deployed on the catheter, the electrodes being configured to transfer radiofrequency (RF) ablation energy to tissue of the organ. The apparatus also includesa power supply configured to supply the RF ablation energy at a level of up to 100W to each of the 10 plurality of electrodes simultaneously, so as to ablate respective sections of the tissue of theorgan in contact with the electrodes.