Rapidly decreasing feature sizes in micro- and nano-electronic devices demand ever higher resolution microscopy tools. The scanning electron microscope (SEM) remains one of the most flexible tools for high-resolution imaging. Modern field emission scanning electron microscopes have a nominal spot size as small as 1 nm, but 1 nm resolution is seldom achieved on ordinary samples due to limitations with beam-sample interactions. The limitations on resolution in the SEM will be discussed, and two methods will be presented which overcome these limitations and enable ultra-high resolution imaging: STEM-in-SEM and low-loss imaging.