Conjugated polymer blends have attracted great interest due to their application as the active layer in a variety of organic electronic devices such as solar cells and light emitting diodes. Although it is well-known that the performance of these devices depends critically upon the nano- and micro-scale morphology of these blends there are few techniques that can directly probe the structure and function of these materials. Near-field Scanning Photocurrent Microscopy (NSPM) is a powerful new technique that allows for two-dimensional mapping of current in fully fabricated organic solar cells. By rastering the light output from a near-field scanning optical microscope tip through a semi-transparent electrode across the solar cell surface it is possible to simultaneously collect height and photocurrent images with a lateral resolution that is governed by the NSOM aperture. Scanning transmission X-ray microscopy (STXM) is an established synchrotron-based technique that is capable of providing chemical contrast in polymer blends with a lateral resolution of better than 50 nm. This talk will show that NSPM and STXM measurements provide a powerful combined probe the relationship between structure and function in photovoltaic devices based on polymer blend solar cell devices.