The Koinonia Principle: Fellowship for a Purpose
What Is Koinonia?
 Isn't koinonia just a new word for the prayer cell idea?
Are there significant results when this plan of agreement is used?
What kind of person should I look for in a koinonia partner?
When or how often should we meet in a koinonia experience?
Are there specifics on how many persons you can experience koinonia with?
Should we serve refreshments?
Are there dangers and problems in koinonia?
What are the benefits of koinonia? 
Rick C. Howard answers these and other questions about koinonia in his book, The Lost Formula of the Early Church--The Koinonia Principle: Fellowship for a Purpose. For example, in answering the last question, Rick Howard comments:
"God provides the method of releasing spiritual atomic energy. Two or more Christians agreeing together have God's promise. This is the foremost benefit. Also, through the study of the Word and sharing, we will grow spiritually. We will see others reached for Christ. We will be a stronger contributor to our church, our family, and our community."
It will take weeks or months to fully experience these glorious truths regarding koinonia, but I feel safe in making two promises to anyone participating:
You need never be lonely because of the blessed fellowship (koinonia) of God's promised plan.
You will always have a purpose in life.
"What wonderful promises!"