reader.go | 2 +-

diff --git a/reader.go b/reader.go
index 9670ff094a8a2ba77f2fd56bbd503757f113fd6b..4b20206cbf2ecc675ccde147cecc278ebc688040 100644
--- a/reader.go
+++ b/reader.go
@@ -12,7 +12,7 @@ 	"github.com/anacrolix/missinggo/v2"
 )
 
 // Accesses Torrent data via a Client. Reads block until the data is available. Seeks and readahead
-// also drive Client behaviour.
+// also drive Client behaviour. Not safe for concurrent use.
 type Reader interface {
 	io.ReadSeekCloser
 	missinggo.ReadContexter