Postsecondary remediation is an important and highly contentious issue that has received comparatively little comprehensive attention with respect to evaluating its effectiveness. This study addresses two relatively unexplored aspects of remedial efficacy: the moderating effects of depth and breadth of underpreparation. I find that, regardless of the depth or breadth of students' initial deficiencies, students who achieve college-level competency in English and math generally exhibit similar levels of attainment. This finding supports the efficacy of remediation even for students who face the greatest deficiencies in English or math and those who have dual deficiencies in both English and math. (Contains 5 tables and 2 figures.)