Available from !%Omega Optical Inc.%! is the FRET Application Note “Optimizing Filter Sets for Fret Applications.” Downloadable from the company Web site, the four-page document begins with an overview of the Förster resonance energy transfer phenomenon. In a discussion on filters and microscope configurations, it notes that two emission filters are required for the process, one for the acceptor and one for the donor fluorophore. Multiview attachments that provide a simultaneous split-screen view of the sample are covered, along with automated emission filter wheels and separate filter cubes. Fluorophore pairs and the company’s FRET filter sets also are addressed. References are provided.