This feature issue of Applied Optics on Digital Holography and 3D Imaging is the sixth of an approximately annual series. At 47 papers, it is the compilation with the largest number of papers so far, including six invited papers. It covers a large range of topics, reflecting the rapidly expanding techniques and applications of digital holography and three-dimensional imaging. For example, phase-shifting methods continue to provide new and powerful holography and interferometry techniques. New approaches are being developed for overcoming difficulties of low coherence holography, while generating high-quality, high signal-to-noise-ratio images. Particle imaging and tracking and biomedical imaging are important areas of powerful applications of digital holography, as well as interferometry and measurements. Compressive imaging is being successfully introduced into digital holography and holds significant potential for efficient processing. Computer-generated holography, integral imaging, and other 3D imaging techniques will have huge impact on the next-generation display technologies. This feature issue contains a large variety of papers in experimental and theoretical studies of these timely topics. Many of the papers in this issue represent in-depth elaboration of topics presented at the recent OSA Topical Meeting on Digital Holography and 3D Imaging (DH), held last April in Miami, Florida. The DH Topical Meeting has been going on ever stronger, continuously for six years, with the next meeting scheduled to be held 21–25 April 2013, in Kohala Coast, Hawaii. We thank and applaud all the authors in this Feature Issue, as well as the participants in the Topical Meeting, for being part of this exciting advance.