A first step in deciphering erased writing is verifying that the erasure has occurred; the second step is studying and reconstructing what has been erased. Sometimes carbon copies of the altered paper, a series of interrelated documents of which the erased one is a dependent unit, or a forgotten photocopy made before the erasure may contain the missing information. Associated evidence of this nature can contain convincing proof of what has been erased. (The term 'associated evidence' embraces all documents which in any way are related to the pertinent copies of the altered ones and may thus assist in its reconstruction.) Several examples emphasize the value of associated evidence. Erasures can be reconstructed from records which are not exact copies of the original. Working backward from the unaltered units or derivatives to the erased 'original' can assist in reconstructing and deciphering. Under favorable circumstances, estimates of when the erasure occurred can be made in relation to when the other writing was placed on the document. In approaching such dating questions, consideration should be given to folds, creases, and perforations in the erased area. The spacing of the writing over the erased area and adjacent unerased lines should also be examined. A case example illustrates the importance of dating information in litigation. One figure and three references are included.