Rounding Problem

Hi all,
Is there any function that truncates a decimal numeric without rounding, if
i use cast it rounds the figure but can i don't want that i.e i want it to
be as follows:
23.1238 turns to 23.123 and not 23.124 so it keeps only three decimals as
is
Please advise if there is any function or so
Thanks in advance
Suad
Try
Round(23.1238,3,1)