Recent legal developments appear to sanction the use of psychometrically unsound procedures for examining differential item functioning (DIF) on standardized tests. More appropriate approaches involve the use of item response theory (IRT). However, many IRT-based DIF studies have used Lord's (1968) joint maximum likelihood procedure, which can lead to incorrect and misleading results. A Monte Carlo simulation was conducted to evaluate the effectiveness of two other methods of parameter estimation: marginal maximum likelihood estimation and Bayes modal estimation. Sample size and data dimensionality were manipulated in the simulation