I recently ran into an issue with embedding youtube videos on my page that would not validate... here is what I did to fix it. Rather than pasting the regular code from youtube which will not validate seen below <object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/RLsteq0ESqk&hl=en_US&fs=1&rel=0&hd=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/RLsteq0ESqk&hl=en_US&fs=1&rel=0&hd=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object> Code (markup): I have pasted this: <object type="application/x-shockwave-flash" width="425" height="350" data="http://www.youtube.com/v/n"><param name="movie" value="http://www.youtube.com/v/n" /></object> Code (markup): where n is the ID number of the relevant YouTube video. If flash is not installed the video will not display so you will want to add this before the </object> <a href="http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash&promoid=BIOW" target="blank"><img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get flash player to play to this file" width="88" height="31" /></a><br /> Code (markup): That will show an image of flash and link back to adobe to have them install the player. Here is what my final code looks like. It will now validate correctly. <object type="application/x-shockwave-flash" width="320" height="265" data="http://www.youtube.com/v/RLsteq0ESqk"><param name="movie" value="http://www.youtube.com/v/RLsteq0ESqk" /><a href="http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash&promoid=BIOW" target="blank"><img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get flash player to play to this file" width="88" height="31" /></a><br /></object> Code (markup):