diff --git a/scm.mes b/scm.mes
index 5b563247..0c14d501 100755
--- a/scm.mes
+++ b/scm.mes
@@ -62,6 +62,12 @@
           (let-loop ,bindings-or-label ,(car rest) ,(cdr rest)))
          (#t (simple-let ,bindings-or-label ,rest))))
 
+(define-macro (do init test . body)
+  `(let loop ((,(caar init) ,(cadar init)))
+     (when (not ,@test)
+       ,@body
+       (loop ,@(cddar init)))))
+
 (define-macro (or2 x y)
   `(cond (,x ,x) (#t ,y)))
 
diff --git a/test.mes b/test.mes
index b417932d..ac2f601f 100644
--- a/test.mes
+++ b/test.mes
@@ -285,6 +285,8 @@
 (pass-if "min 1" (seq? (min 0 1) 0))
 (pass-if "min 2" (seq? (min 1 0 2) 0))
 
+(pass-if "do" (sequal? (let ((acc '())) (do ((i 0 (+ i 1))) ((>= i 3)) (set! acc (cons i acc))) acc) '(2 1 0)))
+
 (newline)
 (display "passed: ") (display (car (result))) (newline)
 (display "failed: ") (display (cadr (result))) (newline)