diff --git a/os2.rkt b/os2.rkt
index b6f9f2d..4381849 100644
--- a/os2.rkt
+++ b/os2.rkt
@@ -221,7 +221,7 @@
 	     (state (struct-copy vm state [pending-actions '()]))
 	     (outbound-actions '()))
     (match remaining-actions
-      ['() (transition state (reverse outbound-actions))]
+      ['() (transition (collect-dead-processes state) (reverse outbound-actions))]
       [(cons (cons pid action) rest)
        (match action
 	 [(at-meta-level preaction)
@@ -230,6 +230,14 @@
 	 [preaction
 	  (loop rest (perform-action pid preaction state) outbound-actions)])])))
 
+(define (collect-dead-processes state)
+  (struct-copy vm state
+	       [processes (for/hash ([(pid p) (in-hash (vm-processes state))]
+				     #:when (or (not (set-empty? (process-endpoints p)))
+						(ormap (lambda (entry) (= (car entry) pid))
+						       (vm-pending-actions state))))
+			    (values pid p))]))
+
 (define (send-to-user failure-proc f . args)
   (with-handlers ([exn:fail? failure-proc])
     (apply f args)))
@@ -293,9 +301,7 @@
 				     [endpoints (set-remove (process-endpoints old-process) eid)]))
     (let ((state (struct-copy vm state
 			      [endpoints (hash-remove (vm-endpoints state) eid)]
-			      [processes (if (set-empty? (process-endpoints new-process))
-					     (hash-remove (vm-processes state) pid)
-					     (hash-set (vm-processes state) pid new-process))])))
+			      [processes (hash-set (vm-processes state) pid new-process)])))
       (for*/fold ([state state])
 	  ([(matching-pid p) (in-hash (vm-processes state))]
 	   [matching-eid (in-set (process-endpoints p))]