Anastylosis (from the Ancient Greek: αναστήλωσις, -εως; ανα, ana = "again", and στηλόω = "to erect [a stela or building]") is an archaeological term for a reconstruction technique whereby a ruined building or monument is restored using the original architectural elements to the greatest degree possible, combined with modern materials if necessary, ensuring that the latter are unobtrusive while clearly recognizable as replacement materials. It is also sometimes used to refer to a similar technique for restoring broken pottery and other small objects. The intent of anastylosis is to rebuild, from as much of the original materials that is left after hundreds or even thousands of years of abuse, historical architectural monuments which have fallen into ruin. This is done by placing components back into their original positions. Where standing buildings are at risk of collapse, the method may entail the preparation of drawings and measurements, piece-by-piece disassembly, and careful reassembly, with new materials as required for structural integrity; occasionally this may include new foundations. When elements or parts are missing, modern materials (of restoration grade) may be substituted, such as plaster, cement, and synthetic resins. The international Venice Charter of 1964 details criteria for anastylosis. First, the original condition of the structure must be confirmed scientifically. Second, the proper placement of each recovered component must be determined. Third, supplemental components must be limited to those necessary for stability (that is, substitute components may never lie at the top), and must be recognizable as replacement materials. New construction for the sake of filling in apparent lacunae is not allowed. Anastylosis has its detractors in the scientific community. In effect, the method poses several problems: No matter how rigorous preparatory studies are, any errors of interpretation will result in errors, often undetectable or incorrigible, in reconstruction. Damage to the original components is practically inevitable.