I found some clever SQL that allows you to strip the Time off of a DateTime in a SQL Server Command.  This has several uses but it makes it simple to use normal Date parameters with DateTime fields and not having to worry about losing the last day due to the times being after midnight.    The SQL would look like this:

DateAdd( day, datediff( day , 0 , YourDateTimeValue) , 0)

One link that describes this method also adds some common date calculations in SQL using similar calculations.

If you need some guidance when it comes to using SQL expressions or commands in your reports, you should get my Expert’t Guide to SQL Expressions, Options and Commands.