Although often treated as a new phenomenon, patron initiated acquisition programs represent the continuation of a long tradition of grass roots collection development – a tradition that many research libraries moved away from as their librarians developed a new-found sense of professional standing in the 1960s and 1970s. The relatively recent re-emergence of patron initiated acquisitions as a key component in the development of research collections has been portrayed as a challenge to that professional standing; yet, the evidence suggests that a well-managed plan can complement the expertise of the subject specialist while effectively meeting the needs of users. Many users either do not know the subject specialist in their field or feel that they often receive the least individualized attention from the subject specialists who ostensibly serve their needs. This paper reviews the results of a pilot project involving a patron-driven acquisitions plan currently employed at one major research institution. Analyzing those items purchased for a variety of disciplines in the humanities, social sciences, and sciences provides a picture of the impact of patron driven acquisitions on research collections. The authors present an assessment of statistics related to circulation, subject emphasis, and consortial holdings from data gathered in these fields. The authors suggest that this collection model is one part of an ever growing suite of services designed to meet “just in time” user needs and can be a particularly useful tool in the development of policies for consortial purchases.