In the early days of e-discovery, what is now commonly called an ESI protocol was usually a relatively short document that specified the agreement between the parties on format for production of electronically stored information (ESI). Other than technical specifications for production images and load files, there was little in the way of detail for how parties would approach the various steps in the discovery process. Today, that has changed. Many ESI protocols cover topics that run the gamut of discovery, from custodians to privilege to production. And many purport to set forth the parties' obligations relating to search and retrieval methodologies—topics that are often a subject of disagreements and motion practice.