Dear all, I am refining my structure (data at 3 A), with a model that is complete. However the Rs values are: R work= 0.25 and Rfree= 0.32. I have read "Improved target weight optimization in phenix.refine" (In the computational crystallographic newsletter 2011) and what I understand is that just by marking the boxes "improve xray/stereochemistry weight" and "improve xray/adp weight" it should work... giving me the best possible Rfree. I'm refining individual coordinates, occupancies, b-factors (isotropic for all atoms), TLS, and using secondary structure restraints, automatic ligand linking and experimental phases restraints. Also, I chose this strategy because I have finished building the structure and according to some of the suggestions in "towards automated crystallographic structure refinement with phenix.refine". I am actually quite confused and don't know what to think... is it a matter of the weights? is it only that this is as good as it gets? Any suggestions and comments are welcome. Thanks a lot in advance, Best, Almudena -- Almudena Ponce-Salvatierra Macromolecular crystallography and Nucleic acid chemistry Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany