The first rule of archiving is to identify the item. Identify early. This might seem obvious, but identifying archive materials may not always be the highest priority in our lives. We all know how it is; you have a stack of productions photos sitting out ready to be labeled and scanned, but you have the production debrief and then auditions and you really just need a few days to decompress, and then you invite that cute girl to come over. You have to straighten up and all those photos or programs or scripts get stuffed into a shoebox and slid under the bed and before you even realize it, years have gone by before you rediscover the forgotten shoebox.
How many times have you looked at an old photo and were unable to remember the name of "so-and-so... you know, that guy with the nose..." As productions open and close, and people come and go, and time marches on, it becomes more and more difficult to remember who did what. If you do not capture that information and record it early it can be lost. And the longer you wait, the harder it is to remember or to dig up the information later.
TIP: Consider including time for documentation in the production schedule and/or including an archivist on your company staff.
"For each production, I assign one of the cast members to be in charge of collecting information - a few programs, a set of headshots, a copy of the script, a press release, etc. It is all put into a manila envelop and labeled. Then after we close and everything has settled down, I can review it in more depth, but I know that the initial information is captured."