This is a timely collection of important biomedical applications for a set of separation/characterization techniques that are rapidly gaining popularity due to their wide dynamic range, high resolution, and ability to function in most commonly used solvent systems. Importantly, the field-flow fractionation (FFF) technique has recently emerged as a prominent complement to size exclusion chromatography for protein pharmaceuticals. Fractionation with FFF is gentle and preserves protein structural integrity better than existing alternatives. In the present text, different chapters are written by experts in their respective field of application, who offer comparisons between the FFF techniques and other methods for characterizing their special focus material. Practical guide-lines for successful implementation, such as choice of operating conditions, are offered in conjunction with each application. In addition to new instrumentation and approaches that address important current topics, readers are provided with an overall sense of prior (but timeless) major developments that may be overlooked in literature searches.