Given the pressure to demonstrate meaningful return from investment in Learning and Development (L&D) interventions, there is an increasing need to reliably evaluate such interventions, both from the point of view of their overall effectiveness (summative approach) and their continuing improvement (formative approach). A literature review, the focus of this conceptual paper, highlights the strengths and weaknesses of various approaches to L&D evaluation. Currently, the most popular methodologies in management practice are the summative-focused frameworks of Donald Kirkpatrick and Jack Phillips. In this paper, their limitations in terms of being able to answer important questions for evaluation are discussed, particularly their failure to take into account a range of factors that influence learning transfer and, thus, learning effectiveness, as well as a lack of guidance on how such interventions could be made better. Arguments for a greater emphasis on formative evaluation are made, and a model for doing so is put forward. Limitations and further research are discussed.