The principle of reversibility: a conservation-restoration treatment must, in principle, be reversible. The conservator should only use products, materials and techniques that do not damage the cultural heritage and that are made specifically for this purpose. His or her intervention must in no way impede or hinder future treatment or investigation.
Taking as one’s starting point respect for the uniqueness and authenticity of the work, every restorative intervention must be reversible. That means that, in principle, it should always be possible to undo it. It must be possible to remove the products used without difficulty. It must be possible to remove retouches unobtrusively and easily.
Although the conservator will always try to conserve using the best available techniques, it is possible that after some time – or even in the foreseeable future – better techniques will be developed and will become available. When that happens it must be theoretically possible to remove the conserving treatment currently applied without damage, so that the improved conservation techniques can be applied.
In line with the principles of conservation in the strict sense, an effort is made to preserve the authentic work of art to the greatest extent possible, even if that means that a number of imperfections remain visible.