diff --git a/README.md b/README.md
index 6e67f37..4a187fd 100644
--- a/README.md
+++ b/README.md
@@ -29,6 +29,7 @@ If your goal is to launch your own tilde-style host (or improve an existing one)
 - [Shell server setup notes](docs/shellserver.md)
 - [SSH key onboarding guide](docs/ssh.md)
 - [Current `/etc/skel` permissions reference](docs/etc-skel-permissions.md)
+- [User and session accounting quick reference](docs/accounting.md)
 
 These documents are focused on practical operations, onboarding, and adding community functionality in safe increments.
 
diff --git a/docs/accounting.md b/docs/accounting.md
index defb715..9a7381b 100644
--- a/docs/accounting.md
+++ b/docs/accounting.md
@@ -1,7 +1,49 @@
 # Accounting
 
-See who has been logged in the longest:
+This page collects simple command-line checks for understanding shell usage on a multi-user host.
 
+## Longest cumulative login time (per user)
+
+The historical one-liner below is still useful, but this version is easier to read and less dependent on shell backticks:
+
+```bash
+users | tr ' ' '\n' | sort -u | while read -r user; do
+  ac "$user" | awk -v u="$user" '{print $1, u}'
+done | sort -n
 ```
-for a in `users`; do echo `ac $a` $a; done|sort|uniq|cut -d' ' -f2,3|sort -n
-```
\ No newline at end of file
+
+### Notes
+
+- `ac` reads connection accounting data (typically from `/var/log/wtmp`).
+- Results are cumulative and depend on log retention.
+- On some systems, log rotation or reboots can make totals look lower than expected.
+
+## Who is currently online
+
+```bash
+who
+```
+
+If you only need usernames:
+
+```bash
+who | awk '{print $1}' | sort -u
+```
+
+## Most recent login for each user
+
+```bash
+lastlog
+```
+
+This is useful for finding dormant accounts and checking recent activity.
+
+## Total command usage summary (process accounting)
+
+If process accounting is enabled, you can summarize command usage:
+
+```bash
+sa
+```
+
+Not all systems enable this by default; if `sa` has no data, verify process accounting configuration first.