Pioneer Outlines 2003 Drilling Program

Pioneer reports that earlier in the quarter, the Company announced a discovery on its Harrier prospect near the Falcon field in the deepwater Gulf of Mexico and today announced in a separate press release that the discovery has been approved for development as a single-well subsea tie-back to its Falcon field. Pioneer has additional prospects on the 32 blocks it holds in the Falcon area and plans to drill two additional exploration wells this year.

Pioneer also announced a joint gas exploration program covering the shallow-water Texas shelf region of the Gulf of Mexico with plans to drill five wells in 2003 and at least three wells in 2004. The first well of the program is currently drilling, and the Company expects to add a second rig to the program during the second quarter.

Drilling operations are concluding on Pioneer's initial exploration prospect in Alaska. Three wells were drilled on the NW Kuparuk prospect to test a possible extension of the productive sands in the Kuparuk River field into the shallow waters offshore. Although all three of the wells found the sands filled with oil, they were too thin to be considered commercial. The wells also encountered thick sections of oil-bearing Jurassic-aged sands that are currently being tested. The first well flowed at a sustained rate of approximately 1,300 barrels per day and will be shut in for a pressure build-up test. The results will be evaluated to determine the commercial viability of the Jurassic reservoir.

Onshore U.S., the Company continues its aggressive development program and is running six rigs in the Permian area, three rigs in the Gulf Coast area and four rigs in the West Panhandle and Hugoton fields. In South Texas, Pioneer has had success in extending the Pawnee gas field with the latest well test flowing 2.5 million cubic feet per day. Additional acreage has been acquired in the area and the Company plans to drill the first well on the new acreage in April. Pioneer is also successfully targeting shallow tight gas sands on its acreage in East Texas. To date in 2003, the Company has drilled 54 development wells onshore U.S. with 29 wells currently producing and 25 wells being completed.

In Canada, Pioneer drilled 16 exploratory wells to test several shallow gas plays. Seven of the wells found multiple gas-bearing zones based on open-hole logs and mud log shows. Unseasonably warm weather resulted in a very short drilling season in Canada, and the wells will have to be tested during next year's winter drilling season. Three wells were drilled to test the Slave Point formation in the Ladyfern field area. One well was successful and is currently being connected to a production pipeline, one well is being evaluated and one well was unsuccessful. In addition, 40 wells were drilled in Canada in the core producing fields with 21 wells connected this season. As a result of winter drilling activities, Pioneer expects its Canadian production to increase by 16 million cubic feet of gas per day net to the Company.

As a result of a successful oil development program in Argentina where Pioneer is running three rigs, daily production rates currently exceed planned volumes. Pioneer plans to drill 40 wells in Argentina during 2003.

In Tunisia, where Pioneer plans to drill at least six wells this year, an exploration well targeting Triassic-aged sands on the Jorf block did not encounter significant hydrocarbons and was abandoned. Pioneer's second well for the year is currently drilling on the Anaguid block, and the Company plans to spud another well on the block within 30 days. Both wells target the same Silurian-aged sands as were found in the Company's Adam discovery. Development of the Adam discovery is progressing with first production expected by early summer. Pioneer plans to begin drilling a well offsetting the Adam discovery in the Borj El Khadra (BEK) block in May and plans to spud another BEK exploration well during the third quarter.

The first of three 2003 exploration wells planned in South Africa is expected to spud in early April on a prospect that is on trend with the Boomslang discovery drilled in 2001.