Fourteen cases of complications from implantation of acrylic fibers into scalps for correction of male-pattern baldness were studied. The complications were severe enough in all of them to force attempts to remove the fibers, many of which from the nature of their knotted insertion could not be extracted. Thus, immediate complications were encountered and serious, delayed, bad effects are anticipated. Among the early complications already observed are marked edema of the face; hemorrhagic oozing; microbial infection; foreign-body reactions; scarring; acneform comedones and pustules; pain, pruritus, and numbness; and loss of natural hair. Complications in the future are likely to be progressive sclerosis from irretrievable fragments and knots of the artificial materials and conceivably malignant degeneration of tissues of the scalp. For all of these known and possible bad effects, implantation of present-day synthetic fibers into the scalp must be judged to be a dangerous practice that must be stopped at once.