Cover picture: Nonlinear excited spectral images of living mouse skin tissue at increasing depths (0-50 μm, scale bar 50 μm). The color matches the emission wavelength. The autofluorescence of the coenzymes NADPH and FAD contribute to the bluish-green color of the epidermal cells while second-harmonic generation is responsible for the purple color of the dermal collagen fibers. At deeper sections (lower panels) small blue spots are visible that correspond to dermal cells. See the article by Palero et al. on page 992.