I\'ve got the following entities on my EDMX :-

These two entites were generated by Update Mode
For proper DB normalization, first thing is that primary keys must be only CountryId and StateId fields - the main Id fields for each table.
And ss I see from the description Name & IsoCode and Name & CountryId should be actually Unique keys, not primary.
Then the model class State should have a field:
public Country Country { get; set; }
Now EF have very good examples and since 4.3.1 + it fully supports Code first / DB first models, which I think will ease solving this. EF 5 have more compatibility updates so I think it wont be a problem for legacy DB engines.