This paper explores the purpose and development of best practice guidelines for the use of preservation metadata as detailed in the PREMIS Data Dictionary for Preservation Metadata within documents conforming to the Metadata Encoding and Transmission Standard, a container format that integrates various forms of metadata with links to digital assets. Integration guidelines are needed to find common practice within the flexibility of METS to serve many different functions within digital systems and to support many different metadata structures. How much needs to be mandated given the different contexts and implementation models in using PREMIS has been an issue for discussion in view of the constant tension between tighter control over the package to support object exchange versus each implementation's unique preservation metadata requirements. The PREMIS in METS Guidelines serve primarily as a submission and dissemination information package standard. This paper details the issues encountered in using the standards together, and how the METS document changes as events pertaining to the lifecycle of digital assets is recorded for future preservation purposes. The guidelines have enabled the implementation of an exchange format based on the PREMIS in METS guidelines, especially tools being developed to support such a standard.