"Fluorescence imaging is a powerful technique that has transformed our understanding of biology. Recently, a number of techniques have been developed that overcome one of the fundamental limitations of fluorescence imaging, namely the diffraction limit. With these techniques, it is now possible to resolve sub-cellular architecture in multiple colors and 3D with unprecedented detail. However, the main limitation of these techniques has been the slow acquisition times making it difficult to study dynamic processes. Since biological samples are inherently highly dynamic, this limitation is a major hurdle that needs to be overcome. I will develop a correlative fluorescence imaging technique that combines the capabilities of super resolution and real-time imaging. With this correlative technique it will be possible to observe the dynamics of a biological sample in real-time and subsequently “freeze” the dynamics (by fixation or low temperature) at a time of interest to obtain a super resolution image. The dynamics can therefore be correlated with ultrastructural information, combining the capabilities of real-time and super resolution imaging. I will apply this correlative imaging technique to study infection mechanism of Herpes Simplex Virus (HSV). HSV is a medically important virus that infects neurons and epithelial cells. Besides the health hazards that it poses, HSV also has important implications in gene therapy. However, the details of HSV infection mechanism remain poorly understood. Since HSV infection involves dynamic interactions between virus particles and sub-cellular components, both of which are tens of nanometers in length scale, this is an ideal model system in which the correlative super resolution and real-time imaging technique will lead to important insights that were previously unattainable."