There are an endless number of solutions.
The basic concept is to make sure that the tables that you are looking to reference from your main table are on the "one" side of your "one-many" relationships.
There also has to be a field on the main report that matches the key field on the reference table. Also, ensure that the key field on the reference table is unique.
If your main table is projects and your looking to reference contractors, ensure that contractors are referenced on your projects table in a common field.
Example:
Projects Table - record 1
Project (field): A
Contractor (field): 1<-- "this would be the common field"
Contractors Table- record 1
Contractor (field): 1(key field)<--
Name (field): John Smith
1 Contractor - Many Projects
Key field(Contractor)
Now you can bring over "look-up" fields to the Projects table from the Contractors table that reference the contractors.
Projects Table - record 1
Project (field): A
Contractor (field): 1
Related Projects (field): 1
Contractors - Name: John Smith
