diff --git a/pacman-project/constants.rkt b/pacman-project/constants.rkt
index 552a169..3039992 100644
--- a/pacman-project/constants.rkt
+++ b/pacman-project/constants.rkt
@@ -33,6 +33,9 @@
           sprite-scale-key
           sprite-scale-key-ui
 
+          ;; Movement
+          pacman-speed-ms
+
           ;; Animation
           animation-interval-ms
 
@@ -93,6 +96,9 @@
     (define sprite-scale-key 1.5)
     (define sprite-scale-key-ui 3)
 
+    ;; Movement speed: time between automatic movement ticks
+    (define pacman-speed-ms 200)
+
     ;; Animation timing
     (define animation-interval-ms 100)