diff --git a/doc/man/timew.1.in b/doc/man/timew.1.in
index c9da3d3c..7737835d 100644
--- a/doc/man/timew.1.in
+++ b/doc/man/timew.1.in
@@ -123,6 +123,21 @@ interval syntax, supported hints, date and duration formats. For example:
   $ timew help date
   $ timew help duration
 
+.TP
+.B timew join @<id> @<id>
+Joins two intervals, by using the earlier of the two start times, and the later
+of the two end times, and the combined set of tags. Using the 'summary' command,
+and specifying the ':ids' hint shows interval IDs. Using the correct IDs, you
+can identify an intervals to join. For example, show the IDs:
+
+  $ timew summary :week :ids
+
+Then having selected '@1' and '@2' as the intervals you wish to join:
+
+  $ timew join @1 @2
+
+See also 'split', 'lengthen', 'shorten'.
+
 .TP
 .B timew lengthen @<id> [@<id> ...] <duration>
 The 'lengthen' command is used to defer the end date of a closed interval.