 <p>If I understand correctly, you can hook into the Form Closing event.</p> <p>So in your main form you can do something like:</p> <pre><code>Form2 form2 = new Form2(); form2.Show(); form2.FormClosing += new FormClosingEventHandler(form2_FormClosing); void form2_FormClosing(object sender, FormClosingEventArgs e) { this.Show(); } </code></pre>