The Kondo effect is investigated by methods developed in the theory of fields with strong coupling. Renormalizability relations analogous to the scaling laws in the theory of second-order phase transitions are found. The behavior of the scattering amplitude of an electron by an impurity is analyzed as a function of the electron energy. Formulas are derived for the resistance as a function of the temperature and for the magnetic moment as a function of the magnetic field and temperature. For the antiferromagnetic interaction sign the resistance tends to a constant and the magnetic moment to zero as T → 0 according to power laws with universal exponents that depend only on the spin of the impurity. For sufficiently large spin the susceptibility tends to infinity as T → 0.