The frontispiece image shows tumor (green) at the microscopic level in living mice. Within the tumor, blood vessels in red are easily visible. When targeted, nanoparticles (quantum dots, shown in white) bind as aggregates in a similar way to three different types of tumor (one example is shown at bottom left). However, when controls are used, very little binding takes place as shown in the other images. Data indicate that vascular targeting may be a robust and reliable method to promote nanoparticle accumulation in a tumor, as opposed to extravasation, which is shown to be highly heterogeneous. For more information, please read the Full Paper “Dynamic Visualization of RGD-Quantum Dot Binding to Tumor Neovasculature and Extravasation in Multiple Living Mouse Models Using Intravital Microscopy” by S. S. Gambhir and co-workers, beginning on page 2222.