This paper proposes a genetic distance measure based on the coancestry coefficient (θ) for populations diverging solely due to drift. The authors construct three estimators of the distance D = -ln(1 - θ) for multiallelic, multilocus data. Simulations of monoecious populations mating randomly show that a weighted ratio of single-locus estimators performs better than unweighted averages or least squares estimators. Jackknifing over loci provides satisfactory variance estimates of distance values. The weighted estimator of D appears to be a better measure of distance than other measures in the literature, especially in the drift situation where mutation is excluded. The paper also compares various distance measures, including those proposed by BALAKRISHNAN and SANGHVI, NEI, and LATTER, and discusses the properties of the estimators under the pure drift model. The results highlight the advantages of the weighted ratio estimator in terms of bias and variance, making it a preferred choice for estimating genetic distance in drift situations.This paper proposes a genetic distance measure based on the coancestry coefficient (θ) for populations diverging solely due to drift. The authors construct three estimators of the distance D = -ln(1 - θ) for multiallelic, multilocus data. Simulations of monoecious populations mating randomly show that a weighted ratio of single-locus estimators performs better than unweighted averages or least squares estimators. Jackknifing over loci provides satisfactory variance estimates of distance values. The weighted estimator of D appears to be a better measure of distance than other measures in the literature, especially in the drift situation where mutation is excluded. The paper also compares various distance measures, including those proposed by BALAKRISHNAN and SANGHVI, NEI, and LATTER, and discusses the properties of the estimators under the pure drift model. The results highlight the advantages of the weighted ratio estimator in terms of bias and variance, making it a preferred choice for estimating genetic distance in drift situations.