You must already have a clearance, or the OP's company must be willing to pay thousands of dollars for you to get one. A TS clearance is not something that can

You must already have a clearance, or the OP's company must be willing to pay thousands of dollars for you to get one. A TS clearance is not something that can simply be applied for. Yes, you fill out the SF86 (for a TS clearance), but your clearance must be sponsored by your current employer or your to-be employer. You cannot fill out the SF86 and mail it in expecting to get a clearance without a sponsoring organization. TS clearances require a rigorous background investigation on the applicant and sometimes require 1 or more polygraphs. The entire investigation/adjudication process can take up to a year or more. The intelligence community that will adjudicate you is trying to determine whether or not you are a risk to the country if you are given classified information. Clearances are very difficult to get, and people are often disqualified because they have poor credit history or have lied on their SF86 (especially about drug use). This is why people that hold a clearance command a premium on their salary. Current figures are that TS-cleared individuals make up to $15K more than their non-cleared counterparts.