A passport is mandatory for any travel outside U.S and passport is the only identity of the citizenship that is acceptable outside country.
American citizens do not require an entry permit or Visa to enter many countries. The U.S. Government's passport service takes a complete 3 weeks to process all applications for issue of passport. It could take longer depending on the other aspects like the location and valid mandatory documents for the passport application. Issue of new passports require the fulfilment of certain conditions such as the applicant must be above the age of 16. Replacement or renewal of passports is considered in case the original was lost or has expired after 15 years of issue, or there is a request to incorporate a name change. Occasionally does an emergency situation arise when one needs to issue a passport within a short period, for e.g. when some unforeseen trip has emerged all of a sudden or when one has to travel for business. For such emergency passports, the applicants are required go through either of the 2 options available depending on the urgency.
First option is to contact the Regional Passport service which issues fast passports to the U.S. Citizens, who genuinely require the passport immediately. Because of the urgency, even if the applicants do not have a prior appointment, they can reach the regional passport office and request to issues passport urgently.
Such applicants, when they get in touch with the regional passport service, their applications will be processed rapidly and the U.S. passport service will take care to issue passport in about 10 days. Now the second option - There are organizations who have established utility services for the issuing passports for people living far away from main cities where the Regional Passport Services are located. They can be approached round the clock through the week to ensure that you get your passport in time. Such agents who endorse to acquire emergency passports have a lot of reputation and a name for efficiency and have also earned a name in the good books of the U.S. State Department. There is an added advantage to this option as travellers can obtain even a travel visa along with their passports which avoids further trouble of visiting the embassy of the country of visit. There are as many as or even more than 40 expediting services and they are all recognized by the U.S. Government. The web site of the U.S. Passport Issue lists their names with contact details. They also present an overview of their credentials over past thirty years to record their significant performance which is displayed at Passport Service For getting fast passports, they work towards a process time improvement from over 3 weeks to less than 10 working days. Among all these, there are some firms which are better than others and achieve the award of passport within a day. Some of the select few passport expediting services are recommended for getting passport still faster. Such firms are given this status based on their service rendered for over 30 years. Here the emphasis is how professional are they in precisely assessing the genuineness of the need and collecting the application form along with mandatory documents.

The most important thing to know is, the agencies charge a minimum of 150 $ or even more for the issue of passports within 24 hours.