The HADDOCK web server is a data-driven biomolecular docking tool that enables the modeling of biomolecular complexes. It allows users to input the structures of individual components and a list of interacting residues, and then generates docking solutions based on experimental or predicted data. The server supports a wide range of experimental data, including NMR, X-ray, and mutagenesis data, and provides multiple web interfaces for different levels of user control. The HADDOCK server utilizes a dedicated cluster and the e-NMR GRID infrastructure, enabling efficient docking runs that typically take a few minutes to prepare and several hours to complete. HADDOCK is a data-driven docking method that incorporates experimental information about the interface region between molecular components and their relative orientations. It supports nucleic acids, small molecules, and various types of experimental data, including NMR distance restraints. The 2.0 version of HADDOCK supports conformational changes in molecules during complex formation and directly supports the docking of NMR structures and other PDB structures containing multiple models. The HADDOCK server has been widely used and has performed well in the CAPRI blind docking experiments, achieving high accuracy in predicting biomolecular interactions. It is currently the most cited biomolecular docking program and has been licensed to over 650 laboratories worldwide. The server provides a user-friendly interface for the most common applications, such as docking driven by CSPs, mutagenesis data, or bioinformatic interface predictions. It also offers advanced interfaces for users who need more control over the docking process, including the ability to upload custom restraint files. The HADDOCK docking protocol involves three stages: rigid-body energy minimization, semi-flexible refinement in torsion angle space, and final refinement in explicit solvent. The server automatically generates the topology of the molecules and allows users to customize parameters such as the number of structures, scoring weights, and temperature. The HADDOCK server is available at http://haddock.chem.uu.nl/Haddock and requires registration for non-profit users. It also offers a GRID-enabled version for users with valid certificates. The HADDOCK server supports a wide range of biomolecules, including proteins, nucleic acids, and small molecules, and allows for the simultaneous docking of up to six molecules. It has been used to model various biomolecular complexes, including protein-protein, protein-nucleic acid, and protein-small molecule interactions. The server provides detailed results, including clustered docking solutions and HADDOCK scores, which can be used to evaluate the accuracy of the docking predictions. The HADDOCK server is a valuable tool for researchers in structural biology and has been widely adopted for its accuracy and efficiency in predicting biomolecular interactions.The HADDOCK web server is a data-driven biomolecular docking tool that enables the modeling of biomolecular complexes. It allows users to input the structures of individual components and a list of interacting residues, and then generates docking solutions based on experimental or predicted data. The server supports a wide range of experimental data, including NMR, X-ray, and mutagenesis data, and provides multiple web interfaces for different levels of user control. The HADDOCK server utilizes a dedicated cluster and the e-NMR GRID infrastructure, enabling efficient docking runs that typically take a few minutes to prepare and several hours to complete. HADDOCK is a data-driven docking method that incorporates experimental information about the interface region between molecular components and their relative orientations. It supports nucleic acids, small molecules, and various types of experimental data, including NMR distance restraints. The 2.0 version of HADDOCK supports conformational changes in molecules during complex formation and directly supports the docking of NMR structures and other PDB structures containing multiple models. The HADDOCK server has been widely used and has performed well in the CAPRI blind docking experiments, achieving high accuracy in predicting biomolecular interactions. It is currently the most cited biomolecular docking program and has been licensed to over 650 laboratories worldwide. The server provides a user-friendly interface for the most common applications, such as docking driven by CSPs, mutagenesis data, or bioinformatic interface predictions. It also offers advanced interfaces for users who need more control over the docking process, including the ability to upload custom restraint files. The HADDOCK docking protocol involves three stages: rigid-body energy minimization, semi-flexible refinement in torsion angle space, and final refinement in explicit solvent. The server automatically generates the topology of the molecules and allows users to customize parameters such as the number of structures, scoring weights, and temperature. The HADDOCK server is available at http://haddock.chem.uu.nl/Haddock and requires registration for non-profit users. It also offers a GRID-enabled version for users with valid certificates. The HADDOCK server supports a wide range of biomolecules, including proteins, nucleic acids, and small molecules, and allows for the simultaneous docking of up to six molecules. It has been used to model various biomolecular complexes, including protein-protein, protein-nucleic acid, and protein-small molecule interactions. The server provides detailed results, including clustered docking solutions and HADDOCK scores, which can be used to evaluate the accuracy of the docking predictions. The HADDOCK server is a valuable tool for researchers in structural biology and has been widely adopted for its accuracy and efficiency in predicting biomolecular interactions.