Conservation picture framing is a specialized, yet semi-industrial art. It is practised by a bewildering array of qualified and unqualified experts, all possessing and proffering a multitude or views, standards, opinions and qualifications. Nevertheless, in spite if of the diversity of views, skills and practices, there are several obvious, unambiguous and distinct framing methods and materials which are .. anathema to any half-decent, self-respecting, practising conservation picture framer. First of these is using any kind of household or industrial tapes to tape, or hold into place, customers' artwork anywhere inside or outside the picture frame. These tapes have adhesives which not only tend to fail with time, but also tend to stain, mark and burn artwork. A conservation hinging tape must be used and the artwork is hinged, rather than taped. Second is using M.D.F. .. (Medium Density Fibreboard) or plywoods or cardboards or newspapers as backing materials which may touch or come into contact with customers' artwork. These materials may emit gases and, to varying saturations, contain highly acidic lignin, which embrittles, stains and discolours artwork when ambient heat and light are present. Third is fitting a picture frame's glazing material (glass or plastic) directly touching, pressing or in contact with the artwork. A window mat (or window mount) should be used to separate, or come in between, the artwork and the pane of glazing material. This will prevent any moisture transferring to the artwork should condensation occur due to temperature an humidity variations. Damp or moist papers and artwork are susceptible to irreversible damage from mould and foxing. There are many other errors and mistakes that people (and picture framers) perpetrate to valuable artwork whilst framing, however the ones explained herein are the most grievous. It is a saddening oxymoron that poor quality materials, unsealed picture frames and inferior picture framing techniques are the most common causes and effect of damaged artwork. More advice, tips and information, particularly on how not to damage valuable art by taping it is found in our Picture Framing Fallacies page.