hi, is it necessary to define the look up at the table? or can i just make a relantionship out of it?

example:

tblA and tblB, both appear in tblC

so should i define the lookup on tblC or should i let the relationship take care of it>?

Most of us would recommend against the table level lookup field:

http://www.mvps.org/access/lookupfields.htm

thanks. cause am trying to do the access 2010 that can be used both as a native client and web at the same time. their web compatability requires you to do the lookup at table level for the relationships.