diff --git a/README.md b/README.md
index 769c029..39adcb2 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,30 @@ post-quantum cryptography and governance documents, the STARK verifier port spec
 their explicit caveats), the formal verification coverage reports, the reproducible-build and
 cross-client determinism documents, and the reproducibility manifest.
 
+## Scope, stated up front
+
+Aere Network runs post-quantum signature verification natively on mainnet: Falcon-512 (`0x0AE1`),
+Falcon-1024 (`0x0AE2`), ML-DSA-44 (`0x0AE3`), SLH-DSA-128s (`0x0AE4`) and SHAKE256 (`0x0AE5`)
+have been live as precompiles since block 9,189,161. You can call them yourself against
+`https://rpc.aere.network` without asking us for anything.
+
+**Consensus on chain 2800 is classical secp256k1 ECDSA QBFT.** The post-quantum work lives at the
+signature, precompile, account and transport layers. Nothing in this repository makes the consensus
+post-quantum, and nothing in it should be read as claiming so. Where you see post-quantum consensus
+discussed, it is research about what a future activation could look like, not a description of the
+running chain.
+
+Two further limits worth knowing before you judge anything else here:
+
+- `0x0AE6` (ML-KEM-768) and `0x0AE7` (Falcon HashToPoint) are **testnet only**. They are not
+  active on mainnet.
+- The on-chain zero-knowledge verifiers are classical BN254. They are broken by Shor's algorithm
+  like any other elliptic-curve construction, and we do not describe them as quantum-safe.
+
+The network is operated by seven Foundation-run validators, so its Nakamoto coefficient is
+effectively one today. That is a real limitation, it is on the roadmap, and it is not fixed by any
+code in this repository.
+
 ## Start here
 
 - `REPRODUCE.md` the single reproducibility manifest. It lists real paths, real commands, and