Each year the International Classification of Diseases, Ninth Edition creates new ICD9-CM codes and modifies existing codes. In the past there has been a grace period from October of each year to January of the new year. This grace period is no longer allowed and effective October 1, 2005 the new ICD9-CM codes are effective and in place. Discontinued codes, modified codes, and new codes are to be observed immediately as of October 1, 2005. Use of the out dated codes will result in claim denials, or returned claim data requesting the updated and appropriate codes. Make certain that any encoding software utilized is properly and updated in a timely manner. Hardcopy ICD9-CM books should be replaced with current publications. It is always a good idea to hold on to any old hardcopy publications of ICD9-CM you may have for future reference when working with any coding issues from the past.