need help with data validation pls

[cherrydee]

I have a sheet called 'codes list' and it has 2 tables. First is 'UACS' which contains codes like 0001, 0002, 0003, etc. and a second table called description which contains the equivalent description of the code. example 0001 - Repair and maintenance, 0002 - office supplies, 0003 - travel expenses, etc.
Now i would like a dropdown in my main index sheet which the user will select from a dropdown a UACS code and the next column should reflect the description of that code. Anyone kind enough to help me? Thanks. I'm going to upload this on docs.google.com for others to encode so I'm not sure if any vba codes will work online.

[sandy666]

A2 - DV list of your codes
B2 - INDEX(description_range,MATCH(A2,code_range,0))

Better would be if you attach example excel file