We have obtained radial velocities of three K giants and one faint carbon star in LGS 3, a dwarf companion of M31, based on 12 individual spectra obtained with the HIRES spectrograph on the Keck I telescope. The mean precision of these measurements is 3.8 km s~1. The mean systemic velocity of LGS 3 is [282.2^3.5 km s~1. Monte Carlo simulations that take into account the individual velocity uncertainties and the maximum observed velocity di †erence reveal that the central velocity dispersion of

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... GS 3 is in the range 2.6È30.5 km s~1, with 95% conÐdence ; the most likely value for the central dispersion is km s~1. These results agree with the kinematics of H I gas in LGS 3. This contrasts with the 7.9~2 .9 5.3 tendency for the gas and stars in other low-luminosity Local Group dwarfs to exhibit distinct spatial and kinematic properties. Taking into account the relative youth of LGS 3, we conclude that the "" asymptotic ÏÏ M/L ratioÈthe value the galaxy would exhibit if it were composed only of ancient starsÈis M/L V,LGS3 º 11 (at a 97.5% conÐdence level), with a most probable value of These values are consistent with the 95~5 6 175. ratios observed in other well-studied early-type dwarfs of the Local Group. We have also estimated M/L V the mass of LGS 3 using modiÐed Newtonian dynamics. These data represent the Ðrst moderately high precision optical spectra of giants in a dwarf system beyond the Galactic halo. We suggest future studies that are now feasible to study the dynamics of dwarf galaxies throughout the Local Group and beyond. ÈÈÈÈÈÈÈÈÈÈÈÈÈÈÈ 1 Based on observations obtained at the W. M. Keck Observatory, which is jointly operated by the