WELS and LCMS
What are the differences between the Lutheran Church--Missouri Synod and Wisconsin Evangelical Lutheran Synod? And, as a follow-up, is it true that Lutherans from different synods cannot take Communion in a Wisconsin Synod church?
The main differences fall in the categories of church and ministry, the application of fellowship principles and the roles of men and women.
There are many essays on the Wisconsin Lutheran Seminary Essay File that provide a history of the relationship between the two synods. This link will take you to those essays.
You might also be interested in A Tale of Two Synods, a book that is available from Northwestern Publishing House.
The Wisconsin Evangelical Lutheran Synod enjoys fellowship with 31 Lutheran church bodies throughout the world. That fellowship includes the privilege of receiving the Lord’s Supper together. This link will take you to a listing of those churches.