Abstract: The crystal structure of human MAPKAP kinase-2 is described, including the high-resolution X-ray diffraction structure and atomic structure coordinates obtained therefrom. A method of crystallization of MK-2 involving the use of a crystallization additive and the specific empirical conditions involved in this crystallization method is also described. This method of crystallization allows a resolution of about 3 Angstroms to be achieved. The tertiary structure of this protein as determined by X-ray crystallography to a resolution of 3 Angstroms is shown. Also described are methods by which the atomic structural information obtained from the MK-2 crystals can be used to screen for, identify and/or design new drugs.