A lattice Monte Carlo scheme for simulating dendrimers that is widely referenced in the literature is that of Mansfield and Klushin (Macromolecules 1993, 26, 4262). However, we show that this scheme does not obey a detailed balance and propose a modification to the original scheme that fixes this problem. To demonstrate the importance of detailed balance to the simulation results, we calculate the radius of gyration and structure factor for ideal dendrimers using our improved model and compare our results to Mansfield and Klushin's original scheme and exact analytical calculations. Excellent agreement is found between our model and the exact analytical calculations, while surprisingly large discrepancies are found between Manfield and Klushin's original scheme and the exact calculations. Our study highlights the importance of detailed balance generally to Monte Carlo simulations of dendrimers and the need to check previous results for nonideal dendrimers obtained from nondetailed balance schemes; we discuss the extension of our model to the nonideal dendrimer case.