Clean it! This deceptively simple directive is usually issued with admirable goals in mind. Layers of corrosion, dirt, pigeon droppings, peeling protective coatings, and graffiti all too often cosmetically disfigure outdoor sculpture, monuments, and similar structures, and can lead to increased rates of material degradation. But when historic or cultural properties are to be cleaned, the rule should be primum non nocere - first, do no harm. The simple, thus, becomes more complex. The cleaning procedure selected must preserve and protect the work by minimizing damage to its historic surface, in terms of preventing removal of original material, inducing the least possible stress, and reducing the degree of warpage and surface roughness that will occur. Equally important, there must be a clear appreciation of the aesthetic qualities and of the material characteristics of the specific object that is to be treated. Only then can the probable interaction between material and method be properly anticipated. In the last two decades, a new approach to the cleaning of statues and other important historic and cultural properties - airbrasive blasting - has become increasingly more evident in the treatment repetoire which includes washing, chemical stripping, and other standard cleaning techniques. In actuality, the basic procedure of airbrasive blasting has been in existence and in use for more than a century, with many of the performance parameters and advantages of this techniques noted in industrial literature since its inception. With the recent developments in high resolution electron optical instruments and other sophisticated analytical tools, the various characteristics of airbrasive cleaning have been able to be examined more scientifically and evaluated more reliably.