The federal definition of emotional disturbance (ED) includes a social maladjustment (SM) exclusion clause that stipulates that students are not eligible for special education services if they are determined to be "socially maladjusted" and not also meeting criteria for ED. This clause has long been criticized for being ambiguous and confusing. Although the clause is not defined in federal regulations, it remains in each new reauthorization of the Individuals With Disabilities Education Act (most recent, Individuals With Disabilities Education Improvement Act [IDEIA], 2004). This study provides an updated review of state practices regarding the use and interpretation of the clause, which has not been conducted since 1994. We examined state definitions, clarifications to terminology, and assessment recommendations to determine whether inconsistencies continue to exist across states. We present the results of a national survey that examined state and local school professionals’ reported practices regarding the exclusion and compared it with the policy of the state in which each respondent resides. Results indicated that states are moving toward the adoption of the federal definition of ED, which includes the clause. This is the case even though state regulations, and staff-reported use and knowledge of the clause continue to be inconsistent across states.