  The recent detections of cosmic shear signal announced by several groups have
demonstrated the feasibility of this challenging program and convinced astro-
nomers of its potential for cosmology. Cosmic shear analysis demands to handle
Gigabytes of data in order to probe several square degrees in subarcsecond deep
imaging mode. The success of these surveys is sensitive to the designs of the
observation strategy, the organization of the data reduction pipelines and the
links of the data base with surveys like X-ray or spectroscopic follow up. We
describe the cosmic shear surveys we have carried out at the VLT and at CFHT
and the way we handle this huge data set in a more general context including
the VIRMOS and the XMM-LSS surveys, and the future CMB surveys.
