--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -2049,6 +2049,19 @@ A jump table for the options with a shor
 			with system specific functions.
 
 
+						*'cryptmethod'* *'cm'*
+'cryptmethod'		number	(default 0)
+			local to buffer
+			{not in Vi}
+	Method used for encryption when the buffer is written to a file:
+		0	PkZip compatible method.  A weak kind of encryption.
+			backwards compatible with Vim 7.2 and older.
+		1	Blowfish method.  Strong encryption.  Not compatible
+			with Vim 7.2 and older.
+	When reading an encrypted file 'cryptmethod' will be set automatically
+	to detected method for the file being read.
+
+
 						*'cscopepathcomp'* *'cspc'*
 'cscopepathcomp' 'cspc'	number	(default 0)
 			global
@@ -4141,7 +4154,7 @@ A jump table for the options with a shor
 			local to buffer
 			{not in Vi}
 	The key that is used for encrypting and decrypting the current buffer.
-	See |encryption|.
+	See |encryption| and 'cryptmethod'.
 	Careful: Do not set the key value by hand, someone might see the typed
 	key.  Use the |:X| command.  But you can make 'key' empty: >
 		:set key=