Clayton Williams Energy Revises Cost Estimate for Drilling Rig JV

Clayton Williams Energy, Inc. revised its previously reported cost estimate related to the formation of a joint venture with Lariat Services, Inc. to acquire 12 new drilling rigs. The total acquisition cost of the rigs is now expected to be approximately $75 million. The previous estimate of $55 million did not include all components and support equipment necessary to place the rigs in service. The Company still expects the rigs to be available for service at various times from March 2006 to December 2006.