TS/SCI, decoded: Top Secret is the clearance, SCI is the access

"TS/SCI" is the most-requested line on cleared job postings and the most misunderstood. Candidates treat it as a single, higher-grade clearance that sits one rung above Top Secret. It isn't. TS/SCI is two separate things written as one: a Top Secret clearance eligibility, and access to Sensitive Compartmented Information that you've been formally read into. You can hold Top Secret without SCI. You cannot hold SCI without Top Secret-level eligibility underneath it.

Getting the distinction right matters at hiring time, because "TS with SCI eligibility," "full-scope TS/SCI," and "collateral TS" describe genuinely different things, and a recruiter who knows the difference can tell instantly whether a candidate read their own clearance correctly.

This is general, factual information about how SCI access works. It is not legal, security, or career advice. SCI eligibility and access are governed by the Director of National Intelligence and granted by the relevant agency under official policy. For your own situation, your Special Security Officer (SSO) or FSO and the official sources linked at the end are the authority.

Top Secret is a level. SCI is a control system.

Top Secret, Secret, and Confidential are classification levels. They describe how much damage unauthorized disclosure would do to national security. Top Secret is the highest of the three, and the clearance ladder post walks through all of them.

SCI is not a fourth, higher level. Sensitive Compartmented Information is classified information about intelligence sources, methods, and analytical processes that has to be handled inside formal access-control systems established by the Director of National Intelligence. It's a way of compartmenting information that is already Top Secret (sometimes Secret), so that holding a TS clearance alone doesn't get you in. You have to be separately approved for the specific compartment.

The official term for everything outside those control systems is collateral. Collateral Top Secret is "regular" Top Secret: you're cleared to the level, with a need-to-know, but you're not read into any compartment. The moment a program puts its information into an SCI control system, collateral TS stops being enough on its own.

So the accurate way to read the label:

• Top Secret (collateral): eligible to access TS information, no SCI.
• TS/SCI: TS eligibility plus indoctrination into one or more SCI compartments.
• TS/SCI with a polygraph: the above, plus an agency-specific polygraph layered on top. More on that below.

What "compartmented" actually means

SCI is divided into control systems and compartments, organized roughly around the kind of intelligence involved — signals intelligence, imagery, human intelligence, and others. Being "TS/SCI" does not mean you can see all of it. You're read into the specific compartments your work requires, and nothing else. Someone read into a signals-intelligence compartment has no access to an unrelated human-intelligence compartment unless they're separately briefed into that one too.

This is why "I have a TS/SCI" is an incomplete statement to a security officer. The real questions are which control systems you've been indoctrinated into, whether those accesses are current, and whether they're verifiable in the system of record. For the Intelligence Community, that system of record is Scattered Castles — the authoritative database for SCI access verification, the IC's counterpart to DISS on the collateral side.

How you actually get SCI access

The path runs through the same machinery as any national-security clearance, with an extra layer at the end. The investigation tiers post explains the investigation behind a clearance; SCI sits at the top of it.

1. Tier 5 investigation. SCI eligibility requires the most extensive background investigation in the Federal Investigative Standards — a Tier 5, the same one Top Secret runs on.
2. Adjudication under ICD 704 and SEAD 4. Eligibility is governed by Intelligence Community Directive 704, the DNI's standard for SCI access. ICD 704 explicitly applies the same 13 SEAD 4 adjudicative guidelines used for collateral clearances, plus a few threshold criteria specific to SCI: you must be a U.S. citizen, and the standard weighs whether close family or associates could expose you to foreign duress.
3. Indoctrination and the SCI NDA. Once you're approved for a compartment, a Special Security Officer "reads you in": a briefing on the nature of the information and the rules for protecting it, and your signature on the SCI nondisclosure agreement (Form 4414), sometimes called the SCI oath. You sign one for the access, and you sign out when you debrief.
4. Continuous evaluation. ICD 704 requires ongoing personnel-security and counterintelligence evaluation for everyone with SCI access — consistent with the move to continuous vetting across the system.

The part candidates underestimate: SCI access follows a billet. You don't apply for SCI the way you apply for a driver's license. An agency or a contract with an SCI-level requirement sponsors the access because the work needs it. That's why "how do I get TS/SCI on my own" doesn't really have an answer — covered more in the sponsorship post.

The polygraph is a separate question

This is where the ladder ClearMatch models — TS/SCI, TS/SCI with CI poly, TS/SCI with full-scope poly — comes from, and it's worth being precise.

A polygraph is not part of SCI by default. ICD 704 leaves it to each IC element: an agency "may require polygraph examinations when the head of an IC element deems it to be in the interest of national security." Some agencies poly everyone with SCI access. Many DoD SCI billets require no polygraph at all. Two flavors come up most:

• Counterintelligence (CI) scope polygraph. Focused on a narrow set of national-security topics: espionage, sabotage, terrorism, unauthorized disclosure of classified information, and unreported foreign contacts.
• Full-scope (or "lifestyle") polygraph. The CI topics plus personal-conduct areas. Agencies like NSA and CIA are well known for requiring full-scope examinations for many positions.

A candidate with "TS/SCI, CI poly" and one with "TS/SCI, full-scope poly" are not interchangeable for a role that demands the full-scope. The polygraph is part of how cleared employers filter, which is why it's a tier in its own right, not a footnote.

SCI is not the only compartmented world

One more distinction that confuses candidates: Special Access Programs (SAPs) are a separate compartmentation system from SCI. SCI is the Intelligence Community's, governed by the DNI. SAPs are primarily the Department of Defense's, with their own access rosters and "briefed-in" process. Both sit above collateral Top Secret, both compartment information beyond the clearance level, and a person can hold collateral TS, SCI, and SAP access in different combinations. If a posting asks for "TS/SCI with SAP eligibility," it's asking for two distinct compartmented accesses, not a typo.

Common myths

• "TS/SCI is a higher clearance than TS." No. The clearance level is the same Top Secret. SCI is access layered on top, granted compartment by compartment.
• "Everyone with TS/SCI has a polygraph." No. The poly is agency-specific and discretionary under ICD 704. Plenty of TS/SCI holders have never sat for one.
• "My SCI transfers anywhere automatically." Reciprocity is the goal across the IC, and a current, verifiable eligibility usually transfers — but being read into a specific compartment at a new organization is a separate step the gaining SSO controls.
• "SCI eligibility never expires." Access is tied to need. When you leave the billet, you debrief and the access is administratively withdrawn, even though your underlying TS eligibility may remain current.

What this means at hiring time

Three practical things:

• Read your own clearance precisely. "TS/SCI" plus the specific control systems you're current in, plus any polygraph, is the accurate statement. Vague is worse than modest here — security officers verify against Scattered Castles and DISS.
• A collateral TS is not a TS/SCI. If a role requires SCI and you hold collateral Top Secret, you meet the level but not the access. Whether that's a fast read-in or a non-starter depends on the program and the billet.
• The polygraph requirement is a hard filter. A role demanding a full-scope poly will not accept a CI-poly candidate without a new examination, and the timeline for that can be long.

What this looks like inside ClearMatch

ClearMatch models clearance the way cleared hiring actually treats it: as a tier, from Confidential up through TS/SCI and the CI-poly and full-scope-poly layers above it — not as a single text string. When you set "TS/SCI with CI poly," the matcher reasons about which roles you actually meet and which need a higher access layer, and it explains the gap instead of burying you in roles you can't take or hiding ones you can.

It does not see your Scattered Castles record or your compartment list, and it doesn't ask which programs you're read into. The agent's job is to find roles where your clearance level and polygraph status fit the requirement, then say why. The read-in is between you, the gaining SSO, and the program.

Sources: ICD 704 — Personnel Security Standards and Procedures Governing Eligibility for Access to SCI (ODNI), ICD 703, SEAD 4 — National Security Adjudicative Guidelines, and the SCI Nondisclosure Agreement (Form 4414). SCI access policy is set by the DNI and implemented by each agency; for your own case, consult your SSO or FSO and the official sources above.