Adding PictureBox on top of another

How to put one picturebox on top of the other; so that the secondly put picturebox having higher priority. like this; Assume there are 2 different pictureboxes(PictureBox1 & PictureBox2) are there in a form, with 2 different images in it. When i put PictureBox2 on top of PictureBox1; it will cover the PictureBox1.So only the PictureBox1 is Showing! thats OK But; When i put PictureBox1, on top of PictureBox2; it will again shows the PictureBox2. (PictureBox1 goes under to the PictureBox2) how to stop this matter. what i want is to be the most recently added picturebox should be on top of the other! When i put PictureBox1, on top of PictureBox2; it should appear PictureBox1: (Since it is the most recently added picturebox) How to achive this! need help thank you