Sports-related concussions, which have become more prevalent in the past decade, are an extremely common phenomenon in organized athletics and create a substantial economic burden on the health care system. Furthermore, they can have devastating impacts on the athletic careers and long-term health of athletes. However, concussion evaluation remains a controversy with respect to diagnosis, management, and return-to-play guidelines for sports-related concussions. This is especially true of the immediate evaluation of sports-related concussion on the sidelines, where decisions must be made quickly and effectively with limited diagnostic resources. Considerable effort has been directed toward developing reliable and valid sidelines assessment modalities for concussion evaluation with a goal of accurately determining whether an athlete requires rapid removal from or is able to return to competition. This paper discusses the role of the concussion specialist on the sidelines during athletic competition and examines the current tools and resources available for the sidelines assessment of concussion. Additionally, new technologies, including electronic applications for Smartphones and tablets, as well as future directions in sidelines assessment of concussion are examined.