Skyline is a freely-available, open-source Windows client application for building Selected Reaction Monitoring (SRM) / Multiple Reaction Monitoring (MRM), Parallel Reaction Monitoring (PRM - Targeted MS/MS and DIA/SWATH) and targeted DDA with MS1 quantitative methods and analyzing the resulting mass spectrometer data.Skyline helps users select peptides and transitions based on mass spectra from their own experiments or imported from public proteomics data repositories (MacLean et al., Bioinformatics 2010; 26:966). Registration required.