Objective -This article presents the findings of a project which established an empirical basis for evidence based library and information practice (EBLIP). More specifically, the paper explores what library and information professionals experienced as evidence in the context of their professional practice.Methods -The project consisted of two sub-studies. The public library sub-study was conducted using ethnography. Over a 5-month period, a member of the research team travelled to a regional public library on 15 occasions, staying between 3 and 4 days on each visit. The researcher observed, interacted, and became involved in the day-to-day activities of this library. These activities were recorded in a journal and added to the researcher's insights and thoughts. Additionally, 13 face-to-face interviews with staff in positions ranging from the operational to the executive were conducted. The academic sub-study was conducted using Constructivist Grounded Theory. Semi-structured interviews were conducted either in person or via Skype, with 13 librarians from Australian universities. Interviewees were in a diverse array of roles, from liaison librarian to manager and library director.Results -The project found that the Australian academic librarians and the public librarians who participated in the project experienced six elements as evidence: observation, feedback, professional colleagues, research literature, statistics, and intuition. Each of these will be described and highlighted with examples from each of the two studies.Conclusions -The findings of this study revealed many similarities in the way that library professionals from both studies experienced evidence. Evidence was not hierarchical, with evidence from many sources being valued equally. In contextualizing evidence and applying to the local environment, library professionals were able to draw upon more than one source of evidence and apply their professional knowledge and experiences. In this way evidence was more nuanced.