HADDOCK is a versatile information-driven flexible docking approach for the modelling of biomolecular complexes. HADDOCK distinguishes itself from ab-initio docking methods in the fact that it can integrate information derived from biochemical, biophysical, or bioinformatics methods to enhance sampling, scoring, or both. HADDOCK supports the incorporation of data from NMR and other biophysical methods, e.g., MS cross-linking and mutagenesis data, to drive the modelling process and the use of SAXS and IM-MS data to filter docking solutions.