diff --git a/prospect/core.rkt b/prospect/core.rkt
index 49ef0b2..ab03fdf 100644
--- a/prospect/core.rkt
+++ b/prospect/core.rkt
@@ -33,6 +33,7 @@
 
          event?
          action?
+         match-event
 
          meta-label?
 
@@ -125,6 +126,11 @@
 (define (event? x) (or (patch? x) (message? x)))
 (define (action? x) (or (event? x) (spawn? x) (quit-network? x)))
 
+(define-syntax-rule (match-event e clause ...)
+  (match e
+    clause ...
+    [_ #f]))
+
 (define (prepend-at-meta pattern level)
   (if (zero? level)
       pattern
@@ -153,19 +159,20 @@
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (define (general-transition? v)
-  (or (not v) (transition? v) (quit? v)))
+  (or (not v) (transition? v) (quit? v) (void? v)))
 
 (define (ensure-transition v)
   (if (general-transition? v)
       v
-      (raise (exn:fail:contract (format "Expected transition, quit or #f; got ~v" v)
+      (raise (exn:fail:contract (format "Expected transition, quit, #f or (void); got ~v" v)
 				(current-continuation-marks)))))
 
 (define (clean-transition t)
   (match t
     [#f #f]
     [(quit exn actions) (quit exn (clean-actions actions))]
-    [(transition state actions) (transition state (clean-actions actions))]))
+    [(transition state actions) (transition state (clean-actions actions))]
+    [(? void?) #f]))
 
 (define (clean-actions actions)
   (filter (lambda (x) (and (action? x) (not (patch-empty? x)))) (flatten actions)))
diff --git a/prospect/examples/bank-account.rkt b/prospect/examples/bank-account.rkt
index f5a0f8a..8c55d5a 100644
--- a/prospect/examples/bank-account.rkt
+++ b/prospect/examples/bank-account.rkt
@@ -5,22 +5,19 @@
 (struct deposit (amount) #:prefab)
 
 (define (manager e balance)
-  (match e
+  (match-event e
     [(message (deposit amount))
      (transition (+ balance amount) (patch-seq (retract (account balance))
-                                               (assert (account (+ balance amount)))))]
-    [_ #f]))
+                                               (assert (account (+ balance amount)))))]))
 
 (define (observer e _)
   (when (patch? e) (for [(balance (project-assertions (patch-added e) (account (?!))))]
-                     (printf "Balance changed to ~a\n" balance)))
-  #f)
+                     (printf "Balance changed to ~a\n" balance))))
 
 (define (updater e _)
-  (if (and (patch? e) (trie-non-empty? (patch-added e)))
-      (quit (list (message (deposit +100))
-                  (message (deposit -30))))
-      #f))
+  (when (and (patch? e) (trie-non-empty? (patch-added e)))
+    (quit (list (message (deposit +100))
+                (message (deposit -30))))))
 
 (spawn manager 0 (patch-seq (assert (observe (deposit ?))) (assert (account 0))))
 (spawn observer (void) (assert (observe (account ?))))