ZD

Zd or ZD may refer to:


 * Nissan ZD engine, an automobile engine
 * Zero Defects, a management program to eliminate defects in industrial production, popular in American industry in the late 1960s
 * Zero-defects mentality, in which a command-and-control structure does not tolerate mistakes
 * Zertifikat Deutsch, a certificate of German language ability
 * Ziff Davis, a magazine publisher and Internet information provider
 * Zooey Deschanel, an American actress and musician