Research on the efficacy of sensory integration therapy (SIT) is addressed in this article. Initially, past key reviews of intervention studies until 1994 are considered. Subsequently, more recent studies from 1994 until 2007 are examined. Consistent with numerous previous reviews, no robust evidence supporting the efficacy of SIT was found. Alternative and more parsimonious explanations for purported effects of SIT are considered. In light of the accumulated lack of evidence for the effectiveness of SIT, continued use of the technique outside of research contexts does not appear to be justified.