  We study Friedel oscillations in one-dimensional electron liquid for
arbitrary electron-electron interaction and arbitrary impurity strength. For
Luttinger liquid leads, the Friedel oscillations decay as x^-g far away from
the impurity, where g is the interaction constant. For a weak scatterer, a
slower decay is found at intermediate distances from the impurity, with a
crossover to the asymptotic x^-g law.
