diff --git a/docs/ENVIRONMENT.rst b/docs/ENVIRONMENT.rst
index e799b2a..5bfb9f4 100644
--- a/docs/ENVIRONMENT.rst
+++ b/docs/ENVIRONMENT.rst
@@ -63,6 +63,9 @@ These environment variables are optional:
   Must be a *NET* from one of the **Coin** classes in `lib/coins.py`_.
   Defaults to `mainnet`.
 
+  Please note that for Bitcoin Core 0.13.1+ there is a special *NET* for
+  testnet: `testnet-segwit`.
+
 * **DB_ENGINE**
 
   Database engine for the UTXO and history database.  The default is