Summary: We derive an estimator of the asymptotic variance of both single and multiple imputation estimators. We assume a parametric imputation model but allow for non- and semiparametric analysis models. Our variance estimator, in contrast to the estimator proposed by D.B. Rubin [Multiple imputation for nonresponse in surveys. (1987)], is consistent even when the imputation and analysis models are misspecified and incompatible with one another.