Knowing the difference between health service evaluation, audit and research can be tricky especially for the novice researcher. Put simply, nursing research involves finding the answers to questions about “what nurses should do to help patients,” audit examines “whether nurses are doing this, and if not, why not,”1 and service evaluation asks about “the effect of nursing care on patient experiences and outcomes.” In this paper, we aim to provide some tips to help guide you through the decision-making process as you begin to plan your evaluation, audit or research project. As a starting point box 1 provides key definitions for each type of project.