BrightLine series fluorescence filter lines now include sets specifically for Fluorescence Resonance Energy Transfer (FRET) imaging applications. These new sets are designed for the most popular live-cell compatible FRET fluorophore pairs: blue-to-green, cyan-to-yellow, and green-to-red fluorescent proteins (including new monomeric red fluorescent proteins such as mCherry). The sets work well with a variety of other fluorophore donor-acceptor pairs. Each set consists of one excitation filter, one dichroic beamsplitter, and two emission filters, so they are suited for the motion-insensitive detection FRET requires in microscopes that are outfitted with an emission filter wheel or with a dual-camera detection module.