Planning for endodontic access should be as precise as possible and the dentist should consider several factors in his preoperative evaluation of teeth to avoid perforations. Anatomical characteristics of teeth can be helpful in establishing endodontic access, and valid and invalid points for orientation have been discussed. Seven suggestions have been offered for the establishment of access on difficult teeth. The ideal in establishing endodontic access can only be achieved by the deliberate, conscious application of a thorough knowledge of dental anatomy, and of possible variations from the norm, coupled with a thorough preoperative examination of the tooth. Although a casual approach may not be unsuccessful, precision will certainly yield a higher percentage of successful cases.