Chapter 2 of the Joint Travel Regulations (JTR), titled “Standard Travel and Transportation Allowances,” establishes the core framework for compensating travelers for normal expenses incurred while under official travel orders. The chapter details the three major categories of standard allowances: transportation, per diem, and miscellaneous reimbursable expenses. It prescribes the rules for selecting, authorizing, and reimbursing various transportation modes—including commercial air, rental vehicles, and privately owned vehicles (POVs)—while emphasizing the mandatory use of U.S. flag carriers and coach-class accommodations unless specific, documented exceptions apply. Furthermore, it provides comprehensive guidelines for calculating per diem allowances, which cover lodging, meals, and incidental expenses based on the authorized t ...