ENVI Classic ROIs are not associated with any one particular image, but are just addresses that can be applied to any image with the same dimensions as the image used to define the ROIs. So, an ROI doesn't have any image data associated with it per se. You can display any image with the appropriate dimensions, and then overlay the ROIs based on those image dimensions. There is not a way in ENVI to apply a decision tree only to an area within an ROI. But there may be a way to get what you want, if you can provide more details about your goals. If you want an image that shows only the decision tree results in the area of a ROI, then you could apply the decision tree to the whole scene, and then apply a mask based on your ROI to that result. That would give you an image containing all background pixels, except in the area of the decision tree, which will have the class results. Is that what you are wanting? Peg Exelis VIS