This paper examines how immigrant enclaves influence labor market outcomes. We examine the effect of ethnic concentration on both immigrant earnings and employment in high immigration states using the non-public use, 1-in-6 sample of the 2000 U.S. Census. Although we find that there is some variability in the estimated enclave effects, they exhibit an overall negative impact. Male and female immigrants from several ethnic groups tend to earn lower wages when residing in areas with larger ethnic concentrations. Similarly, for employment, most of the statistically significant effects are negative, although much smaller than the enclave impacts on earnings.