diff --git a/src/ikarus.boot b/src/ikarus.boot
index 1c93710..8205ef5 100644
Binary files a/src/ikarus.boot and b/src/ikarus.boot differ
diff --git a/src/ikarus.lists.ss b/src/ikarus.lists.ss
index 6f537c5..4e23508 100644
--- a/src/ikarus.lists.ss
+++ b/src/ikarus.lists.ss
@@ -2,13 +2,13 @@
 (library (ikarus lists)
   (export $memq list? list cons* make-list append length list-ref reverse
           last-pair memq memp memv member assq assp assv assoc
-          remq remv remove remp map for-each andmap ormap list-tail)
+          remq remv remove remp filter map for-each andmap ormap list-tail)
   (import 
     (ikarus system $fx)
     (ikarus system $pairs)
     (except (ikarus) list? list cons* make-list append reverse
             last-pair length list-ref memq memp memv member assq
-            assp assv assoc remq remv remove remp 
+            assp assv assoc remq remv remove remp filter
             map for-each andmap ormap list-tail))
 
   (define $memq
@@ -391,7 +391,7 @@
          (race x ls ls ls))))
 
 
-  (module (remq remv remove remp)
+  (module (remq remv remove remp filter)
     (define-syntax define-remover 
       (syntax-rules ()
         [(_ name cmp check)
@@ -432,7 +432,11 @@
     (define-remover remp (lambda (elt p) (p elt))
       (lambda (x ls) 
         (unless (procedure? x)
-          (error 'remp "~s is not a procedure" x)))))
+          (error 'remp "~s is not a procedure" x)))) 
+    (define-remover filter (lambda (elt p) (not (p elt)))
+      (lambda (x ls) 
+        (unless (procedure? x)
+          (error 'filter "~s is not a procedure" x)))))
 
 
   (module (map)
diff --git a/src/makefile.ss b/src/makefile.ss
index be2cf84..4f46188 100755
--- a/src/makefile.ss
+++ b/src/makefile.ss
@@ -332,6 +332,7 @@
     [remp                    i]
     [remv                    i]
     [remove                  i]
+    [filter                  i]
     [list-sort               i]
     [vector-sort             i]
     [vector-sort!            i]
diff --git a/src/todo-r6rs.ss b/src/todo-r6rs.ss
index 63caf1f..f7fc248 100755
--- a/src/todo-r6rs.ss
+++ b/src/todo-r6rs.ss
@@ -504,7 +504,7 @@
     [assq                                       C ls se]
     [assv                                       C ls se]
     [cons*                                      C ls]
-    [filter                                     S ls]
+    [filter                                     C ls]
     [find                                       S ls]
     [fold-left                                  S ls]
     [fold-right                                 S ls]
@@ -516,9 +516,9 @@
     [memv                                       C ls se]
     [partition                                  S ls]
     [remq                                       C ls]
-    [remp                                       S ls]
-    [remv                                       S ls]
-    [remove                                     S ls]
+    [remp                                       C ls]
+    [remv                                       C ls]
+    [remove                                     C ls]
     ;;;
     [set-car!                                   C mp se]
     [set-cdr!                                   C mp se]
@@ -792,12 +792,6 @@
                         libs))))
     (error #f "invalid id ~s" x)))
 
-(define (filter p? ls) 
-  (cond
-    [(null? ls) '()]
-    [(p? (car ls)) 
-     (cons (car ls) (filter p? (cdr ls)))]
-    [else (filter p? (cdr ls))]))
 
 (define (filter* ls) 
   (filter