With strain imaging, the elastogram is created using either minimal compression or physiologic tissue motion from cardiac pulsations or respiration as the stress force on tissue. Detection pulses track displacement is used to derive a strain image in grayscale or color-coded display. Visual evaluation of grayscale strain image is feasible with a grayscale map according to which the darker the lesion is the higher the stiffness. A lesion size on elastography to the B-mode size ratio was proposed as a diagnostic tool to differentiate benign from malignant breast lesions. This ratio is named EI/B ratio. Semiquantitative way of stiffness evaluation, cysts, strain image in color-coded display, and evaluation of color mapping strain image are some other important topics which are discussed briefly throughout this chapter.