"Cosmology has recently entered a concordance and precision era with its predictions being accurately and successfully tested by a number of observational probes. This status however is achieved at the expense of 96% of the Universe being assumed to be in still unknown forms known as Dark Matter and Dark Energy.CALICE addresses open questions of Cosmology using Gravitational Lensing. This technique describes how light is deflected as it passes through the gravitational field generated by matter. Its effect can be detected in the distorted images of galaxies via a modification of their shapes. This “cosmic shear” effect is a unique probe of the geometry and matter distribution in the Universe. It has however its systematic effects which must be controlled to be efficiently used in future high precision surveys, such as the satellite Euclid mission.Given the current and potential possibilities of cosmic shear, CALICE is divided in two parts. On one hand it will use data from CFHTLS and COSMOS surveys in three key goals. The first is to look for possible deviations of gravity effects from the ones predicted by General Relativity and study their evolution using tomographic measurements. The second is to study Dark Energy by combining lensing with measurements of the variation of the fine-structure constant and the proton-to-electron mass ratio. The third goal is to use the information on the evolution of matter distribution and its properties at large scales, to constrain the neutrinos mass.On the other hand CALICE will contribute to the preparation of future surveys by conducting a study, using numerical simulations, of astrophysical effects that produce correlations in galaxies shapes, which contaminate the measurements. CALICE will produce detail modelling of various correlations as function of galaxy type, satellite distribution, magnitude and distance, creating a template to be used as a reference for removing such contaminations from future data."