This article reviews the recent complex and somewhatc onfusing evidence on writing-to-learn and discusses why this lack of clarity exists. It then draws on the field of cognitive psychology to offer a way to reconceptualize how researchers might approach the study of the impact of writing on learning. This reconceptualization involves a modification in both how researchers select writing tasks and conditions in writing-to-learni nvestigationsa nd how they assess the possible knowledge changes due to writing. In the selection of writing tasks and conditions, it is suggested that researchers draw on theories of knowledge change to guide their selections. Four basic theoretical mechanisms potentially related to knowledge change due to writing are discussed. In the measurement of knowledge change, it is argued that writing may more likely influence structural than reproductive aspects of knowledge. Five methods for assessing structural changes in knowledge due to writing are considered.