Conceptual models provide a theoretical basis for advancing scientific knowledge and improving professional practice. Although numerous assistive technology-related models have appeared in the literature, there has been no systematic effort to assess them. Six conceptual models are reviewed here: Cook and Hussey's Human-Activity-Assistive Technology model; the World Health Organization's International Classification of Functioning, Disability, and Health; Scherer's Matching Person and Technology model; Gitlin's model of an AT user's "career"; social cognition decision-making theories; and Rogers' Perceived Attributes Theory. The models are reviewed in terms of six domains: background and goals; descriptive characteristics; indication of outcome measures; predictive characteristics; validation in the literature; and utility to assistive technology practitioners, developers, and consumers. The salient strengths and limitations are highlighted for each. Application of the models to advance theory, research, and practice is discussed.