diff --git a/README.md b/README.md
index 2c63a45..fd657fa 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,3 @@
-
 # Systems
 
 `systems` is a set of tools for describing, running and visualizing
@@ -68,6 +67,17 @@ systems/
 
 `systems-run` is used to run models:
 
+    $ systems-run --help
+    usage: parse.py [-h] [-r ROUNDS] [--csv] [-R ROUND_TO]
+
+    options:
+      -h, --help            show this help message and exit
+      -r ROUNDS, --rounds ROUNDS
+                            number of rounds to run evaluation
+      --csv
+      -R ROUND_TO, --round-to ROUND_TO
+                            number of digits to round outputs to
+
     $ cat examples/hiring.txt | systems-run -r 3
     PhoneScreens    Onsites Offers  Hires   Employees       Departures
     0       0               0       0       0       5               0
diff --git a/docs/tutorial.md b/docs/tutorial.md
index 52e1a43..22f0756 100644
--- a/docs/tutorial.md
+++ b/docs/tutorial.md
@@ -1,4 +1,3 @@
-
 # Tutorial
 
 Please follow the [installation instructions](../) before continuing with these steps.
@@ -39,9 +38,12 @@ Then you could run the simulation for 10 rounds:
     9       15              45              22      11      5       18              1
     10      15              45              22      11      5       22              1
 
+Sometimes it may be clearer to round the outputs for display:
+
+    systems-run --round-to 2
+
 You can also get the output as CSV:
 
     cat examples/links.txt | systems-run -r10 --csv
 
 Which you could... load into a spreadsheet or something to graph!
-
diff --git a/systems/models.py b/systems/models.py
index b112eda..866bb74 100644
--- a/systems/models.py
+++ b/systems/models.py
@@ -325,7 +325,7 @@ def render_html(self, results):
         rows += ["</tbody>", "</table>"]
         return "\n".join(rows)
 
-    def render(self, results, sep='\t', pad=True):
+    def render(self, results, sep='\t', pad=True, round_to=None):
         "Render results to string from Model run."
         lines = []
 
@@ -338,7 +338,10 @@ def render(self, results, sep='\t', pad=True):
         for i, snapshot in enumerate(results):
             row = "%s" % i
             for j, col in enumerate(col_stocks):
-                num = str(snapshot[col.name])
+                value = snapshot[col.name]
+                if round_to:
+                    value = round(value, round_to)
+                num = str(value)
                 if pad:
                     num = num.ljust(col_size[j])
 
diff --git a/systems/parse.py b/systems/parse.py
index 29d9edc..37ff1d0 100644
--- a/systems/parse.py
+++ b/systems/parse.py
@@ -121,6 +121,11 @@ def main():
         help="number of rounds to run evaluation",
         default=10)
     p.add_argument('--csv', action='store_true', default=False)
+    p.add_argument(
+        '-R',
+        '--round-to',
+        type=int,
+        help="number of digits to round outputs to")
     args = p.parse_args()
 
     txt = sys.stdin.read()
@@ -136,6 +141,8 @@ def main():
     if args.csv:
         kwargs['sep'] = ','
         kwargs['pad'] = False
+    if args.round_to:
+        kwargs['round_to'] = args.round_to
     print(model.render(results, **kwargs))