say i have a site that almost all visitors are webmasters and the keyswords are strong on the niche,what do you do to get ads that would be of interest of them (webmaster ads) without breaking any rules. niche doesn't mater.if the niche was Fluffy Bunny Slippers and your site was about helping people with Fluffy Bunny Slippers sites,you wouldn't want ads that are selling Fluffy Bunny Slippers,would you?
You must use deep keywords in sidebars related to webmasters . If you are using adsense ads pointing html tag than you have to face this because if someone is looking for Fluffy Bunny Slippers and you have added that keyword in post than adds will display .
Try to implement section targeting in order to come up with more relevant ads. However, there's no guarantee it will 100% work but it reduces likelihood that non relevant ads pop up.