Pursuant to the Federal Rules of Civil Procedure 26(b)(2)(B), 26(b)(2)(C), 26(g)(1)(B)(iii), and other federal and state procedural rules, proportionality is the legal doctrine that states that ESI may be withheld from production if the cost and burden of producing it exceed its potential value to the resolution of the matter. Proportionality has been interpreted in the case law to apply to preservation and production. This doctrine is vital to limiting the boundaries of discovery as data volumes explode in our modern digital era.