There is often the effect of time upon a stain: the older the stain, the harder it is to remove. Drycleaners who are trained in stain removal prefer to work on fresh stains which have not had time to "set" or react with the fabric, dyes, finish, or atmosphere. Generally, a stain less than two months old can be treated; a stain one-day-old is easier than one that is two-weeks-old, etc.