diff --git a/plugins/inputs/procstat/README.md b/plugins/inputs/procstat/README.md
index 0c37af509..90552c2a6 100644
--- a/plugins/inputs/procstat/README.md
+++ b/plugins/inputs/procstat/README.md
@@ -7,7 +7,8 @@ individual process using their /proc data.
 
 The plugin will tag processes by their PID and their process name.
 
-Processes can be specified either by pid file or by executable name. Procstat
+Processes can be specified either by pid file, by executable name, by command
+line pattern matching, or by username (in this order or priority. Procstat
 plugin will use `pgrep` when executable name is provided to obtain the pid.
 Proctstas plugin will transmit IO, memory, cpu, file descriptor related
 measurements for every process specified. A prefix can be set to isolate