  There are two possible mechanisms to imprint planet signatures in the
chemical composition of Sun-like stars: i) dust condensation at the early
stages of planet formation, causing a depletion of refractory elements in the
gas accreted by the star in the late stages of its formation; ii) planet
engulfment, enriching the host star in lithium and refractory elements. We
discuss both planet signatures, the influence of galactic chemical evolution,
and the importance of binaries composed of stellar twins as laboratories to
verify abundance anomalies imprinted by planets.
