Longitudinal Data Systems (LDS) house student data spanning multiple years and schools. First and foremost among LDS information resources is the Data Quality Campaign (DQC). The DQC is a nationwide consortium assembled to support states, districts, and schools as they design and implement data systems to improve student outcomes. The research and resources in this paper have been divided into three categories: (1) Necessity; (2) Implementing; and (3) Utilizing. This paper is a response to a request asking for a bibliography of the seminal pieces of research related to ARRA Assurance #2--Longitudinal Data Systems.