PatchDock and SymmDock are two freely available web servers for molecular docking. PatchDock predicts the structure of protein-protein and protein-small molecule complexes by finding transformations that yield good molecular shape complementarity. SymmDock predicts the structure of homomultimers with cyclic symmetry given the structure of the monomeric unit. Both servers accept protein PDB codes or uploaded structures and are available at http://bioinfo3d.cs.tau.ac.il. The methods are efficient, allowing large-scale docking experiments. PatchDock is a geometry-based algorithm that divides the Connolly dot surface into concave, convex, and flat patches. Complementary patches are matched to generate candidate transformations, which are evaluated using a scoring function that considers geometric fit and atomic desolvation. The algorithm uses fast transformational search and advanced data structures to improve efficiency. The run time for two average-sized proteins is less than 10 minutes on a single 1.0 GHz PC. The PatchDock web server has a simple interface where users can input two molecules in PDB format. The server generates a web page with the top 20 solutions, including geometric score, interface area size, and desolvation energy. Users can view or download solutions, and there is an option to view additional solutions. The number of solutions can be limited to 100. SymmDock is a geometry-based algorithm for predicting cyclically symmetric complexes. It restricts its search to symmetric transformations and uses the special characteristics of cyclic symmetry in its search and clustering methodologies. The SymmDock web server is simpler, requiring only one molecule and symmetry order as input. It generates a web page with predicted solutions, and each solution is a multimer of the asymmetric unit. The server sends an email with a link to the solutions page. Both servers are efficient and user-friendly, with detailed documentation and support for various types of complexes. They are valuable tools for predicting protein-protein and protein-small molecule interactions.PatchDock and SymmDock are two freely available web servers for molecular docking. PatchDock predicts the structure of protein-protein and protein-small molecule complexes by finding transformations that yield good molecular shape complementarity. SymmDock predicts the structure of homomultimers with cyclic symmetry given the structure of the monomeric unit. Both servers accept protein PDB codes or uploaded structures and are available at http://bioinfo3d.cs.tau.ac.il. The methods are efficient, allowing large-scale docking experiments. PatchDock is a geometry-based algorithm that divides the Connolly dot surface into concave, convex, and flat patches. Complementary patches are matched to generate candidate transformations, which are evaluated using a scoring function that considers geometric fit and atomic desolvation. The algorithm uses fast transformational search and advanced data structures to improve efficiency. The run time for two average-sized proteins is less than 10 minutes on a single 1.0 GHz PC. The PatchDock web server has a simple interface where users can input two molecules in PDB format. The server generates a web page with the top 20 solutions, including geometric score, interface area size, and desolvation energy. Users can view or download solutions, and there is an option to view additional solutions. The number of solutions can be limited to 100. SymmDock is a geometry-based algorithm for predicting cyclically symmetric complexes. It restricts its search to symmetric transformations and uses the special characteristics of cyclic symmetry in its search and clustering methodologies. The SymmDock web server is simpler, requiring only one molecule and symmetry order as input. It generates a web page with predicted solutions, and each solution is a multimer of the asymmetric unit. The server sends an email with a link to the solutions page. Both servers are efficient and user-friendly, with detailed documentation and support for various types of complexes. They are valuable tools for predicting protein-protein and protein-small molecule interactions.