Dear Colleagues,

We are pleased to announce that a *Workshop on Monitoring North American Geoid Change* is going to be held in Boulder, Colorado, USA from October 21 through 23, 2009.

The goal of this workshop is to develop a collaborative plan to use common standards to monitor the geoid model over North America, through a combination of dedicated absolute gravity campaigns and reliance on continued satellite gravity missions. This monitoring is critical to various governments in North America that have begun moving toward a geoid-based determination of their vertical datum.

Experts in absolute and satellite gravity and geoid determination are asked to attend. The few oral presentations will be limited to invited speakers, but an open poster session will be held. A tour of the Micro-G/LaCoste facilities and a tour of the Table Mountain Geophysical Observatory (TMGO) will be included.

* Registration for the workshop is free.
* Hotel and registration information are provided at the URL above.

We look forward to seeing you in Boulder!

Dru Smith and Joe Henton