Again, lot's of good posts.  Shie, Robert L, Noeld, and Adam have all pointed out that the use of a "Calendar Table" or "Holiday Table" to hold non-workdays (I'm assuming neither of these hold M-F normal workdays except maybe when a shift differential must be accounted for, haven't quite figured that one out yet) could be used to augment this function.  I took a look at Paul Cresham's UK Bank Holiday script he posted and it certainly looks like you could use it straight up as is or you could modify it to easily populate several years worth of Holiday table.

The flexibility of Holiday tables (Calendar tables) certainly seems to have some merit although, unless you make a pretty big one, will have some limits whereas the functions are much less limited.  As with many Date/Time calculations, it sometimes takes more than one function/method to get what you want.  In a previous post on this same thread, I suggested that the article should have been called "Calculating Week Days" instead of "Calculating Work Days".  Through the intelligent use of a combination of functions like this one and Paul's, Holiday tables, and perhaps, a shift differential function or embedded calculation, you can build the "ultimate work day calculator" for your particular needs.

Again, thank you all for your feedback.  I don't know if it's true for you but I've sure learned a lot about what people need or have done concerning the true calculation of work days (not usually weekends but sometimes includes Saturdays, not holidays [we all knew that], not bank holidays, sometimes needs to account for shift differentials) especially for areas outside of the U.S.

Just a reminder... this function wasn't designed to do anything except count the number of week days in a date range much like MS-SQL's DATEEPART calculates, well, date parts.  I do appologize for the misnaming of the article.