Prospectus Summary
The following summary is qualified in its entirety by, and should be read in conjunction with, the more detailed information and financial statements, including the notes thereto, appearing elsewhere in this Prospectus. Unless the context otherwise requires, references herein to "Allegiance" and the "Company" refer to Allegiance Telecom, Inc., a Delaware corporation, and its subsidiaries. Unless otherwise indicated, the information contained in this Prospectus: (i) gives effect to the Equity Offering, assuming a public offering price of $ per share and assumes no exercise of the underwriters' over-allotment option and (ii) gives effect to a -for-one stock split of the Company's Common Stock. Certain information contained in this summary and elsewhere in this Prospectus, including information under "Management's Discussion and Analysis of Financial Condition and Results of Operations" and information with respect to the Company's plans and strategy for its business and related financing, includes forward-looking statements that involve risk and uncertainties. Prospective investors should carefully consider the factors set forth under "Risk Factors" and are urged to read this Prospectus in its entirety.