Although turbulent flow separation is an old topic, little credible information is available on the flow details that must be understood to predict flows of this type. Until the last decade, there was little serious effort to develop and use experimental techniques that give unambiguous results. Consequently, flow models that are based on valid data are not well developed. Furthermore, the terminology used in discussing separation has been loosely defined, adding further confusion to the subject. This brief review presents a cross-sectional view of recent experimental techniques and results, development of models for flow prediction, efforts to define a meaningful common terminology to describe the flow, unsteady effects, and efforts to control separation.