diff --git a/pubsub/README.md b/pubsub/README.md
index f3b53d9..7b7faf5 100644
--- a/pubsub/README.md
+++ b/pubsub/README.md
@@ -75,6 +75,13 @@ You can find information about the PubSub research and notes in the following re
   - [gossipsub](https://github.com/libp2p/specs/tree/master/pubsub/gossipsub#implementation-status)
 - [EpiSub](https://github.com/libp2p/specs/blob/master/pubsub/gossipsub/episub.md), an epidemic broadcast tree router (defined 2018, not yet started as of Oct 2018)
 
+## Stream management
+
+Data should be exchanged between peers using two separately negotiated streams,
+one inbound, one outbound. These streams are treated as unidirectional streams.
+The outbound stream is used only to write data. The inbound stream is used only
+to read data.
+
 ## The RPC
 
 All communication between peers happens in the form of exchanging protobuf RPC