diff --git a/button.go b/button.go
index 4e3d7e1..aa1c0bd 100644
--- a/button.go
+++ b/button.go
@@ -42,7 +42,7 @@ func (b *Button) make(window *sysData) error {
 	defer b.lock.Unlock()
 
 	b.sysData.event = b.Clicked
-	err := b.sysData.make(b.initText, 300, 300, window)
+	err := b.sysData.make(b.initText, window)
 	if err != nil {
 		return err
 	}
diff --git a/checkbox.go b/checkbox.go
index 017b81a..dc148e2 100644
--- a/checkbox.go
+++ b/checkbox.go
@@ -53,7 +53,7 @@ func (c *Checkbox) make(window *sysData) error {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
-	err := c.sysData.make(c.initText, 300, 300, window)
+	err := c.sysData.make(c.initText, window)
 	if err != nil {
 		return err
 	}
diff --git a/combobox.go b/combobox.go
index 5080d38..e018cce 100644
--- a/combobox.go
+++ b/combobox.go
@@ -45,7 +45,7 @@ func (c *Combobox) make(window *sysData) (err error) {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
-	err = c.sysData.make("", 300, 300, window)
+	err = c.sysData.make("", window)
 	if err != nil {
 		return err
 	}
diff --git a/label.go b/label.go
index 12cec5b..d924cd3 100644
--- a/label.go
+++ b/label.go
@@ -29,7 +29,7 @@ func (l *Label) make(window *sysData) error {
 	l.lock.Lock()
 	defer l.lock.Unlock()
 
-	err := l.sysData.make(l.initText, 300, 300, window)
+	err := l.sysData.make(l.initText, window)
 	if err != nil {
 		return err
 	}
diff --git a/lineedit.go b/lineedit.go
index a8c9057..9c5b25d 100644
--- a/lineedit.go
+++ b/lineedit.go
@@ -42,7 +42,7 @@ func (l *LineEdit) make(window *sysData) error {
 	l.lock.Lock()
 	defer l.lock.Unlock()
 
-	err := l.sysData.make(l.initText, 300, 300, window)
+	err := l.sysData.make(l.initText, window)
 	if err != nil {
 		return err
 	}
diff --git a/listbox.go b/listbox.go
index b973714..20f1ffd 100644
--- a/listbox.go
+++ b/listbox.go
@@ -36,7 +36,7 @@ func (l *Listbox) make(window *sysData) (err error) {
 	l.lock.Lock()
 	defer l.lock.Unlock()
 
-	err = l.sysData.make("", 300, 300, window)
+	err = l.sysData.make("", window)
 	if err != nil {
 		return err
 	}
diff --git a/sysdata.go b/sysdata.go
index 929c015..a49db08 100644
--- a/sysdata.go
+++ b/sysdata.go
@@ -12,7 +12,7 @@ type cSysData struct {
 	resize	func(x int, y int, width int, height int) error
 	alternate	bool		// editable for Combobox, multi-select for listbox
 }
-func (c *cSysData) make(initText string, initWidth int, initHeight int, window *sysData) error {
+func (c *cSysData) make(initText string, window *sysData) error {
 	panic(runtime.GOOS + " sysData does not define make()")
 }
 func (c *cSysData) show() error {
diff --git a/sysdata_windows.go b/sysdata_windows.go
index 6d56b83..3f20964 100644
--- a/sysdata_windows.go
+++ b/sysdata_windows.go
@@ -102,7 +102,7 @@ func (s *sysData) delChild(id _HMENU) {
 }
 
 // TODO adorn error messages with what stage failed?
-func (s *sysData) make(initText string, initWidth int, initHeight int, window *sysData) (err error) {
+func (s *sysData) make(initText string, window *sysData) (err error) {
 	ret := make(chan uiret)
 	defer close(ret)
 	ct := classTypes[s.ctype]
@@ -130,10 +130,10 @@ func (s *sysData) make(initText string, initWidth int, initHeight int, window *s
 			uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(classname))),
 			uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(initText))),
 			style,
-			uintptr(_CW_USEDEFAULT),		// TODO
 			uintptr(_CW_USEDEFAULT),
-			uintptr(initWidth),
-			uintptr(initHeight),
+			uintptr(_CW_USEDEFAULT),
+			uintptr(_CW_USEDEFAULT),
+			uintptr(_CW_USEDEFAULT),
 			pwin,
 			uintptr(cid),
 			uintptr(hInstance),
diff --git a/window.go b/window.go
index d77fdd0..770cc81 100644
--- a/window.go
+++ b/window.go
@@ -71,7 +71,7 @@ func (w *Window) Open(control Control) (err error) {
 		panic("window already open")
 	}
 	w.sysData.event = w.Closing
-	err = w.sysData.make(w.initTitle, w.initWidth, w.initHeight, nil)
+	err = w.sysData.make(w.initTitle, nil)
 	if err != nil {
 		return fmt.Errorf("error opening window: %v", err)
 	}
@@ -82,7 +82,10 @@ func (w *Window) Open(control Control) (err error) {
 			return fmt.Errorf("error adding window's control: %v", err)
 		}
 	}
-	// TODO resize window to apply control sizes
+	err = w.sysData.setWindowSize(w.initWidth, w.initHeight)
+	if err != nil {
+		return fmt.Errorf("error setting window size (in Window.Open()): %v", err)
+	}
 	// TODO separate showing?
 	err = w.sysData.show()
 	if err != nil {