"The literature on restorative environments has grown rapidly over recent years. This growth has been accompanied by increasing diversity in aspects of the methods used. This holds true in several ways. Researchers are sampling from a broader range of environments, and trying to capture sensory aspects of those environments other than the visual alone. Researchers are also considering a greater variety of antecedent deficits from which people might need to recover, and with them a greater variety of processes through which they can recover the diminished resources. They also are beginning to address the temporal parameters for those recovery processes and the need for valid measures to represent those processes. These developments are encouraging, but this diversification and the concomitant growth in the complexity of the literature also give reason for concern. In this presentation we address two related concerns that have to do with the measurement of cognitive capabilities thought to be sensitive to fatigue, in particular directed attention capacity. First, research has been troubled by questions about how to establish or represent the need for attention restoration which research participants experience prior to the time available for restoration in one or another environment. Second, research on attentional recovery has produced inconsistent results, and it is not certain what this depends on. Possible reasons include, but are not limited to, a lack of any substantial need for restoration on the part of some subjects, a lack of time allowed for restoration, and the use of measures that are insensitive to the theoretically assumed mechanism. The purpose of this presentation is to overview the cognitive measures that have been employed in efforts to detect restorative effects and consider how long the restorative period must endure to give positive outcomes on performance. We begin by describing the different approaches that have been taken to measuring the antecedent condition, the temporal aspects of the restorative process, and the outcomes of the restorative process within discrete restorative experiences. We then look more specifically at approaches used to induce attentional fatigue within experimental studies, and the measures used to establish whether directed attention restoration has occurred. We emphasize outcomes that reflect on actual changes in cognitive resources with restoration, rather than potential changes or variation in variables described in theory as mediators of attentional recovery (i.e. the components of restorative experiences specified in attention restoration theory). The general conclusion we draw is that researchers need to further specify the term "directed attentional fatigue" and the cognitive processes involved in the development of attentional fatigue and recovery from it. We will end the presentation with suggestions from theories within working memory and some ideas for future research. "