The high prevalence of ADHD continues to present a challenge, particularly in high poverty urban schools. Low-income children of color are both more likely to be diagnosed with the disorder and more likely to be under-treated compared to their Caucasian peers. While significant attention is paid to what teachers across a variety of school settings know about ADHD, little is known about school social workers knowledge of ADHD. In addition, little is also known about the collaborative processes by which school social workers support teachers in addressing ADHD in urban schools. Utilizing a mixed-methods survey design, this study explored urban elementary school social worker knowledge of ADHD and inter-disciplinary collaboration processes between school social workers and teachers. Findings indicated that urban elementary school social workers N=43 had strong knowledge of ADHD causes and symptoms. No significant differences were observed when compared to their suburban elementary school colleagues N=24 as measured by The ADHD Belief and Attitudes Scale (Johnston and Freeman, 2002). A directive content analysis of responses for N= 43 urban elementary school social workers further revealed key findings. First, school social workers were able to identify a number of behavioral and instructional strategies applicable to students with attention related difficulties. Secondly, while collaboration between teachers and school social workers may occur during participation in interdisciplinary school teams and informal discussions, time constraints and teacher receptiveness presented as major barriers for consistent and effective collaboration. Given the limited resources of many urban school settings, it would benefit schools to promote the role of the school social worker and collaborative practices with teachers in addressing ADHD and similar disruptive behavior disorders within the classroom.