As e-discovery and new document management techniques become more popular, some attorneys may not retain client information for as long as they should. Generally, files that involve cases with disabled persons, minors, or files containing sensitive original documents should be retained indefinitely. Also, attorneys should be sure to keep information on all current and former clients, including their last known address.
This does not mean that your office will be buried in paper for all time. The Illinois legal malpractice statute (735 ILCS 5/13-214.3) has a two year statute of limitations and a six year statute of repose. This means that you can dispose of most documents after 7 years or so; though you could get rid of many types of documents earlier, 7 years is the safe bet. Additionally, attorneys must retain financial records for at least seven years per Supreme Court Rule 769. It may be smart to keep estate and probate files around a bit longer, depending on the nature and duration of the case.