Identical, unilateral, distal extension base (DEB) maxillary and mandibular casts with a posterior modification area were mailed to 15 Canadian commercial dental laboratories. Each cast was accompanied by a letter explaining the purpose of the study and a request for the laboratory to design a RPD-U and RPD-L framework. The package also included a questionnaire on the techniques commonly used by dentists in the construction of a removable partial denture prosthesis, as well as the laboratory procedures they requested from laboratory technicians. Compared to the findings of previous studies by McCracken and others, the results of this study indicate an improvement in the dentists' understanding of the fundamental principles of an RPD framework design. However, the questionnaire also revealed the need for improved communication between the dentist and the technician. The study suggests that the basic principles for the construction and design of removable partial dentures, as taught in dental schools across Canada, must be respected by dentists.