This is the abstract of our nice paper that will describe the requirements and design concepts of a detector for the FCC-ee accelerator. To do match the fabulous statistical precision of the FCC-ee extremely good detector performnace is required. The detector features a 2 T solenoidal field, will have a ultralight silicon vertex detetor, a large gas drift volume, and electromagnetic and hadronic calorimeter sections. Details will be given also on the luminosity measurement.