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Measurements of parity violation in electron scattering (PVES) have provided a wealth of information on the nucleon and the electroweak interaction. In this kind of experiments the parity violating asymmetry Apv, that is the fractional difference in cross sections for positive and negative helicity electrons is measured. Measuring Apv one can probe the weak force and the structure of the nucleon. A very exciting PVES program was performed at JLab taking advantage of the exceptional features of the CEBAF electron beam. The experiments HAPPEX-
Apv was obtained. HAPPEX series experiments obtained very important results: they showed that the strange contributions to the nucleon form factors are consistent with zero and not more than a few percent of the proton form factors. For the upgrade of the CEBAF beam energy to a maximum of 12 GeV, the new spectrometer SOLID and the experiment MOLLER have been proposed. SOLID will allow measurements in deep inelastic scattering (DIS) simultaneously covering a large kinematic range in both xBj and Q2 and providing consequently new information on a variety of topics including charge symmetry violation, higher twist contribution to proton structure and electroweak coupling constants. The MOLLER experiment will measure the weak charge of the electron with a precision of 2.3% by measuring the parity violating asymmetry in electron-