diff --git a/man/mu-init.1 b/man/mu-init.1
index 1a6f7313..c09d9593 100644
--- a/man/mu-init.1
+++ b/man/mu-init.1
@@ -43,8 +43,9 @@ allows you, for example, to filter out (\fBmu cfind --personal\fR) addresses
 which were merely seen in mailing list messages.
 
 \fI<my-email-address>\fR can be either a plain e-mail address (such as
-\fBfoo@example.com\fR), or a regular-expression (of the 'Basic POSIX'
-flavor), wrapped in \fB/\fR (such as \fB/foo-.*@example\\.com/\fR).
+\fBfoo@example.com\fR), or a regular-expression (of the 'Basic POSIX' flavor),
+wrapped in \fB/\fR (such as \fB/foo-.*@example\\.com/\fR). Depending on your
+shell program, the argument may need to b quoted.
 
 .SH ENVIRONMENT
 
diff --git a/mu4e/mu4e.texi b/mu4e/mu4e.texi
index 048e410c..319f674f 100644
--- a/mu4e/mu4e.texi
+++ b/mu4e/mu4e.texi
@@ -452,7 +452,8 @@ indexing messages. If you want to change them, you need to @t{init}
 once again.
 
 The addresses can also be basic POSIX regular expressions, wrapped in
-slashes, such as @t{/foo-.*@@example\\.com/}.
+slashes, such as @t{/foo-.*@@example\\.com/}. Depending on your shell
+program, the argument may need to b quoted.
 
 If you want to see the current values, you can use @command{mu info}.