PurposeThis paper aims to survey the published journal literature on reference transaction assessment. Its purpose is to highlight the need for a multiple perspectives approach due to the complexity of reference transactions. Satisfaction indicators, behavioral aspects, accuracy rates, success measures, and other desired transaction outcomes contribute to the need for a broader assessment picture.Design/methodology/approachThis is a review from the first decade of the twenty‐first century. Selected were papers from 2001 through 2010, filtered from search results from library literature databases. Primary inclusion criteria identified refereed papers, studies of academic library populations, evaluation or assessment of reference transactions, and methods contributing to systematic practices versus unique assessment events.FindingsBy viewing reference transactions as complex interactions, librarians are recognizing that simple counts and narrow views of assessment are not adequate. Missing in the assessment literature is a universally accepted set of standard approaches, study methodologies, and reporting formats for comparison and analysis. Improvements may contribute to efforts that go beyond local studies to more meaningful peer comparisons.Research limitations/implicationsAlthough not an exhaustive representation of all reference services assessment literature, the paper profiles the heart of reference, i.e. the interaction between users and library service providers. This focus fosters a concentration on a core reference activity: addressing library users' information needs.Originality/valueThis review highlights assessment challenges, unresolved problems, and topics addressed from 2001 to 2010. It also provides a look at tools that can enhance assessment programs.