The transmission electron microscope for analyzing tissue sections and protein samples is another part of the research infrastructure financed by the Higher Education Area Structural Funds program of the Austrian Federal Ministry of Education, Science and Research. This technology is applied to look into the center of cells, tissue and tumors. Three-dimensional electron microscopy allows new insights into different cell organelles, visualizing functional relationships in terms of ultrastructures and thereby making comprehensible the possibilities for medical intervention, for example in tumor biology.