Exhibit 10.1 SUMMARY OF COMPENSATION ARRANGEMENTS FOR RAYMOND G. HEYMAN, SENIOR VICE PRESIDENT AND GENERAL COUNSEL o Annual salary of $280,000. o A grant of options on 50,000 shares of UniSource Energy Corporation Common Stock, with an exercise price set at the Stock's market value on September 15, 2005. o Participation in the UniSource Energy Corporation annual short-term incentive plan at a target bonus of 55 % of salary, and a maximum of 110 % of salary. o Additional benefits available to UniSource Energy Corporation's executive officers generally. COMPENSATION INCREASES FOR CERTAIN OFFICERS o Michael J. DeConcini, Senior Vice President and Chief Operating Officer, Energy Supply, Annual Salary $280,000. o Kevin P. Larson, Senior Vice President, Treasurer and Chief Financial Officer, Annual Salary $280,000.