We will discuss details of vertical datums and geoid models of the NSRS, and illustrate why NAVD88 is being replaced (and without any leveling!). OPUS Static, OPUS Rapid Static, and OPUS Projects (OP) will be covered in detail, including the newest function of integrating RTN/RTK-GNSS data into OPUS Projects. Demonstrations of the NGS Coordinate Conversion and Transformation Tool (NCAT), the NOAA VDatum application, and other online tools will be performed. As always questions and discussions will be welcome, and you are invited to send any specific questions to jeff.jalbrzikowski@noaa.gov ahead of time, to be addressed during the session.