>I would like to collect information as to know how often do you apply a full reindexation of your tables. I have received all kinds of feedback so far but this is not concreate. Some says they are doing it on a weekly basis, some annual and so on. Are you really gaining of seeing an improve of performance when doing that?

Most of my clients do it nightly.

If you're using uniqueidentifier data types as indexes, then you definitely want to do it nightly.

At the very least, tables that regularly receive inserts/updates should be reindexed once a week.

Annual? I think doing it once a year would only make sense for small control tables that are seldom changed during the year.