Frequent Travelers often need a Second Passport to augment their main passport and allow them to travel while one of their passports is being used to obtain a travel visa (which usually "locks up" a passport at the foreign embassy for 2-6 weeks).
You may obtain a Second Passport using the Economical Passport Renew process as easily as getting your main Passport renewed. (You do need to convince the Department of State that you need a Second Passport via a statement letter that you write (and we can help you with))