Exhibit 16 KPMG Peat Marwick LLP 300 North Marienfeld, Suite 300 Midland, Texas 79701 December 19, 1997 Securities and Exchange Commission Washington, D.C. 20549 Ladies and Gentlemen: We are the principal accountants for Pioneer Natural Resources Company and, under the date of January 29, 1997, we reported on the consolidated financial statements of Pioneer Natural Resources Company and subsidiaries as of and for the years ended December 31, 1996 and 1995. On December 5, 1997, our appointment as principal accountants was terminated for periods after December 31, 1997, and after completion of our audit on such fiscal period. We have read Pioneer Natural Resources Company's statements included under Item 4 of its Form 8-K dated December 5, 1997, and we agree with such statements. Very truly yours, KPMG Peat Marwick LLP 5