Hi Carol, We took delivery of a Leica TCS NT system comprising the DMRBE and the matching inverted DMIRBE January 1997. The system also has an Ar UV laser attached. The microscopes are standing side by side (upright on the left and inverted on the right) as recommended by the company. This arrangement allows for the easy transfer of the scanner head from one microscope to the other. I regularly perform this transfer with no difficulty - just a simple exercise of moving the head from the upright, down to the inverted. There has not been any problem with the aligned of the lasers with the repeated change, although I would be reluctant to allow just anybody to do it. Our confocal facility is a multi-user setup and the ability to have 2 lasers and the two different microscopes provides a wide spectrum of application. The head has a bit of weight in it and the unwary user could be unprepared. Having said that, I have also trained other people to do this when I am not there. Vera Dr Vera Terry Department of Anatomy and Histology, F13 University of Sydney NSW 2006 Australia