Luminescent organic crystals often exhibit mechanochromic luminescence (MCL), which refers to the reversible color change of photoluminescence induced by mechanical stimuli such as grinding, crushing, and pressing. Initial developments of mechanoresponsive luminescent crystals relied on serendipity, making the rational design of MCL a challenging task. This chapter reviews recent advancements in tunable MCL of organic crystals. One fundamental strategy involves tuning molecular conformation in the crystalline state by introducing sterically different substituents, which controls the luminescence color and alters MCL properties. Another significant approach is the preparation of two-component organic crystals. Formation of cocrystals and solvates is a fundamental method for tuning the luminescence properties of organic crystals. Additionally, the formation of segregated crystals has proven to be an effective method for achieving MCL with a substantial shift in emission wavelength. Furthermore, the luminescent properties of organic crystals can be finely tuned by preparing mixed crystals containing trace amounts of dopant compounds, and this approach can extend the range of mechanoresponsive luminescence shifts.