The Defensible Dress is a response to the increasing breakdown and encroachment on personal space in everyday life. Historically, each culture and generation has had varying definitions of personal boundaries. Globalization and the urban condition have diminished an understanding of, and respect for, such space. Personal space is increasingly challenged and violated by external pressures. Inspired by the porcupine and the blowfish, the Defensible Dress marks the wearer's personal space by activating a space-defining physical projection around the body. The extents of the personal space zone are defined as a numerical distance by the dress wearer. When infrared sensors detect an approaching body entering the personal space zone, a series of mechanical quills are activated, bristling to prevent encroachment.