Issue classification for reporting

We would like a standard set of classifications the user can pick from so we can lump issues into common categories to identify trends. Categories could be nested in a tree such that each discipline has their own sub categories. Examples of high level categories might be insufficient space, cross-discipline coordination issue, quality concern. omission, etc. Examples of discipline specific items might be pipe support, pipe spec, installation type, etc.  Classifications could match with lessons learned categories.