Disclosed are 3-aryl-6-aryl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles and related compounds thereof, represented by the Formula I: ##STR00001## wherein Ar.sub.1, Ar.sub.2, and X are defined herein. The present invention relates to the discovery that compounds having Formula I are activators of caspases and inducers of apoptosis. Therefore, the activators of caspases and inducers of apoptosis of this invention may be used to induce cell death in a variety of clinical conditions in which uncontrolled growth and spread of abnormal cells occurs.