Over the past year we have developed two similar questionnaires on three-dimensional radiotherapy treatment planning (3DRTP) systems and used them to conduct a study of the function and features of commercially available 3DRTP systems. The issues which we reviewed to develop these questionnaires are important to all current and potential users of 3DRTP systems. The items identified in this article should aid readers in developing their own review questionnaire based on the items we discuss as well as their own clinical practice. Because it is not possible to develop a universal questionnaire that will satisfy every clinic because of site- specific treatment techniques and capabilities, this information should aid an institution contemplating the purchase of such a system to develop their own specific set of questions to aid them in their system selection. We believe that a high-level checklist of this nature will prove quite helpful to those institutions preparing to purchase such a system.