Dysregulated bone remodeling is a major part of the pathology of a number ofdiseases. Disclosed herein is the use of Binding Immunoglobulin Protein (BiP)forthe prevention or treatment of bone diseases or conditions typically involvingboneloss or bone resorption. Corresponding diagnostic methods and assay methods,aswell as pharmaceutical compositions, and methods for their preparation, arealsodisclosed herein.