Abstract: In many organizations advice is routinely given by supervisors to subordinates. The advice literature examines the effects of advice on judgment and decision making. This study extends the advice literature into a practical setting in examining the effects of the timing of supervisory advice on the judgment of subordinate tax professionals in a professional context. An experiment was conducted with 58 tax professionals from public accounting firms across Canada, performing tax planning tasks of different complexity. Supervisory advice is generally given to tax professionals before they commence tax planning tasks but the results of this study demonstrate that this practice could have detrimental effects. First, advice could be beneficial for a higher-complexity task but not for a lower-complexity task. Second, advice given before a tax professional commences a higher-complexity task is found to hinder the insightful judgments often necessary for this task but advice given after the tax professional prepares a tentative solution does not have this negative effect. This study contributes to the behavioral and advice literatures. The results of this research study should also be of interest to hierarchical organizations, including public accounting firms where supervisors routinely provide advice to subordinates performing tasks of differential complexity.