The ACT system is a key-press, menu-driven system for selecting, administering, and storing raw data from a series of specially designed psychological tasks. Associated task analysis programs process the raw data and store the resulting summary data for later statistical analysis. The system utilizes a cognitive approach to assessments of marginal toxicity by employing multiple performance parameters to specify a profile of deficits that, on the basis of a task's internal structure, can be related to functionally discrete cognitive systems. The tasks have been developed from a consideration of current cognitive theory and the areas of cognition include those of learning, memory, attention, reasoning, verbal, and spatial abilities. The ACT system is described in terms of its four major components: the cognitive tasks, the stimulus materials, the analysis methods, and the process of saving and combining summary data into files suitable for transfer to statistical analysis programs. The system thus automates the data collection to statistical analysis process.