Summary of the calorimeter session

At the future linear collider, most of the interesting physics processes have many jets in the final state. For this reason, the design of the calorimeter has to be evaluated through the jets reconstruction (Eflow). In the calorimeter session, about half of the talks were related to Eflow, the second half concerning the hardware side of the studies. All groups agreed on the importance of quantifying the proposed detector through a reconstruction program of the multi-jet events. A first attempt to reconstruct with fully simulated events using the ECFA proposed detector, reached a jet energy resolution of DeltaE(JET) similar to 40%rootE(JET) which seemed mandatory for the very rich physics program on the Linear Collider. It corresponds to a significant improvement when compared to LEP/SLD experiments. To reach this kind of value both ECFA and LCD(US) groups followed the road of sampling calorimeter, with a large number of segmentations and a small pad size. It is not the case of JLC-group which took the road of hardware compensated calorimeter. The hardware studies of the calorimeters have made a lot of progress in the realistic direction. A lot of R&D are foreseen, on the technical side as well as on industrialisation, cost... On the side of hardware compensation, the JLC group, built a prototype and put it on test beam. First results were given and the goal of e/pi = 1 seems at hand.