Mechanical makeover of the tissue microenvironment has emerged as both the cause and the consequence of the breast carcinogenesis. Laser Speckle Rheological microscopy (SHEAR) maps the viscoelastic properties of the tissue microenvironment with high spatial resolution (∼50 μm). The cover displays the SHEAR map of viscoelastic moduli for an invasive ductal carcinoma of the breast featuring the stiff tumor stroma (red to magenta to purple hues) in striking contrast with the soft tumor epithelium (blue to green to yellow hues). In human breast tumors, micromechanical metrics including heterogeneity and gradients of viscoelastic moduli measured by SHEAR are associated with histological subtype, grade, molecular expressions, and nodal status. For details, see the article by Hajjarian and colleagues on page 4874.