I do not want to change/alter the design template. I have one "Master Slide company background master slide" fo a 40-slide presentation. (this is Not a title slide, by the way.) In the middle of this, I simiply want to switch/change to another "Master Slide company background slide" for 5 slides. Then go back to the original PPT Master slide. I would like to copy the 2nd Master Slide background slide & put this into the lineup of Master Slides. But when I copy & paste this new Master Slide -- and then click on it to Select it - and then Close the Master Slide screen - nothing happens to the background of the presentation slides. They are unaffected. Obviously, I'm doing something wrong or not doing something that I should. Can someone please help me? This is enormously frustrating. I thank you all in advance for you kind help! Larry